I love the flavor of the Druid and how the class description presents it.
Here is a running commentary on the description.
DRUID
Primary Ability: Wisdom
Wisdom as Perception, makes sense for animal senses and a class in tune with nature.
As an auxiliary ability, I also get an Intelligence vibe, as the attention to the dynamic complexities of an ecology is sophisticated and precisely technical. There is a wisefolk ambiance of sages, experts, and healers.
Druids belong to ancient orders that call on the forces of nature. Harnessing the magic of animals, plants, weather, and the four elements, Druids can heal, transform themselves, and wield elemental destruction.
I read "forces of nature" to mean animism, and generally the class handles this sacred concept well. I might emphasize even more, the Druid is the member of a community of "neighbors" that include animals, plants, weather, sun, landscape and other elements, who value mutual respect and helpfulness (or at least civility) as neighbors.
The attention is correctly the forces of the nature of the Material Plane.
Revering nature above all, individual Druids gain their magic from a nature deity, from nature itself, or both, and they typically unite with other Druids in performing rites to mark the passage of the seasons and other natural cycles. The ancient druidic traditions are sometimes called the Old Faith, in contrast to the worship of gods
in temples and shrines.
Here the player has a choice of character concepts: animism ("nature itself"), polytheism ("a deity"), or both.
My own interest in the Druid class is animism.
The polytheism is also an option. The historical druids are polytheists, a priestly caste who serve Celtic deities. If D&D is going to appropriate the cultural term "druid", I like that a player can use the class to try represent a mythologically accurate druid. The D&D Druid is more like a mish-mash of the reallife Celtic traditions about druid and bard, plus later fairy tales, and modern environmental concerns. Yet, since the historical druid itself remains obscure and tangled, the D&D versions seem somewhat reasonable enough. A mythologically accurate Druid would be a member of a sacred family, whose members have a choice to serve as a priest. The ordination means a sacred status who disavows the weapons of warriors, but who defends the community by means of magical spells instead. The D&D Druid fighting by wielding weather magic, buffing allies, and attacking in Wild Shape forms have this magical combatant vibe. Apparently, the historical druids held a concept of reincarnation, looked to the clouds in the sky to divinate the future, and may have something to do with brewing potions with sophisticated ingredients and precise timing. The historical druidic priests worship Celtic divinities, and serve as the spiritual leaders of a community, probably functioning much like Irish Catholic priests do today.
The D&D Druid allows options for both the animistic nature beings and the polytheistic divine beings. Consider the general difference between a "nature being" and a "divine being". A river itself is a nature being, a helpful neighbor. By contrast, a separate being who controls and rules over rivers is a divinity, a worshiped master with an institutional personnel of servants.
In D&D terms, nature beings are aspects of the Primal magic of the Material Plane, and divine beings are aspects of the Divine magic of the Astral Plane, especially its Celestial creature type.
The neighborliness of the "Old Faith" means animism, while the "worship of gods in temples" means polytheism. These sacred traditions can be a mix where there are aspects of both. Probably the D&D Druid is always at least partially animistic.
Even in the context of certain Druids who revere a "nature deity", namely an Astral Celestial archetypal ideal, the Druid class seems uninterested in the Astral Plane itself and entirely focuses on the Material Plane. The this-worldly view can be concerned about the Celestial ideals if they seek to materialize within the nature of the Material Plane. Likewise, the Druids generally dont care what is going on in the Feywild or the Shadowfell, but care intensely about how Fey Crossings and Shadow Crossings interfere with the Material Plane.
Druids master primal magic, which is oriented toward nature and animals—the power of tooth and claw, of sun and moon, of fire and storm.
Druids also gain the ability to take on animal forms, and some Druids focus on this practice, even to the point where they feel more natural in an animal form.
Re "Primal magic". Primal magic is the Material Plane.
The D&D Druid tradition has many moving parts across the editions. The game mechanics can be nonsynergizing and a bit all over the place. Yet the class description does a decent job of pulling together all of the facets into a comprehensive whole. It conveys an animistic worldview that attends to the actual features of nature: "the tooth and claw" of animals, the literal sun itself in the sky, the Thunderbird-like storm cloud that people can look up and plainly see. In other words, the Material Plane.
For Druids, nature exists in a precarious balance. The four elements that make up a world—air, earth, fire, and water—must remain in equilibrium. If one element were to gain power over the others, the world could be destroyed, drawn into one of the elemental planes and broken apart into its component elements. Thus, Druids oppose cults of Elemental Evil and others who promote one element to the exclusion of others.
Druids are also concerned with the delicate ecological balance that sustains plant and animal life and with the need for people to live in harmony with nature, not in opposition to it.
Druids are often found guarding sacred sites or watching over regions of unspoiled nature. But when a significant danger arises, threatening nature’s balance or the lands they protect, Druids take a more active role as adventurers who combat the threat.
This part of the Druid class description caught my attention. These tropes about the environmental harmony of the four elements − earth, water, air, and fire − that makes life possible, are central to the Dark Sun setting. WotC seems to discontinue Dark Sun (even literally throw it into a blackhole) mainly because of problematics akin to normalizing slavery. But the compelling, interesting and relevant, environmental tropes seem to be resurfacing within the context of the Druid class.
Dark Sun did many fascinating things about the ecology, how it works and how it failed. Indeed, the Druid class is dedicated to making sure the Dark Sun ecological cataclysm never happens.
In Dark Sun, on planet Athas, the Humans discovered a way to convert the element of water into magical energy. The technique reminds me of nuclear fission converting matter into energy by destroying the atom. The magical process annihilated the existence of elemental water. The absence of water on Athas threw the rest of the elements into chaos: earth, air, and fire. The planetary ecosystem failed, and life is almost extinct.
The setting emphasizes a "Positive Material Plane" and a "Negative Material Plane". The Positive is vestigial areas surviving here and there, where some water survives, making the elemental harmony possible. These locales of harmony allow an influx from the Positive Energy Plane, within which the positivity vitalizes lush plant life and teaming animal life. Within the Material Plane, the positivity becomes life force. Oppositely, the areas where water is utterly absent connects to the Negative [Void] Plane, within which life is extinguished, plants cannot grow, and deathliness prevails within the negativity.
In a 5e context, via the 4e tradition, the Positive Material Plane is the same thing as the Fey Crossings, and the Negative Material Plane is the Shadow Crossings.
Meanwhile, the Athasian Cleric class revered the elements as abstract principles, sacred cosmic forces, in a way resembling Daoist elemental traditions. The Athasian Druid is also elemental but focuses on local natural features such as the sun, rock formations, and remnant pools of water. The features of nature are psionically resonant. So some rock formations and so on are powerful mental presences, in an animistic way. These places where life thrives are "sacred sites of unspoiled nature", and the Druids guard them.
The 5e Druid class description evokes the Dark Sun concepts. "Nature exists in a precarious balance. The four elements that make up the world − air, earth, fire, and water − must remain in equilibrium." "Druids are also concerned with the delicate ecological balance that sustains plant and animal life."
I appreciate the following 5e Druid attitude because it is humanist. It seeks "the need for people to live in harmony with nature". A Human and other Humanoid civilization can synergize with wild nature. It isnt human versus nature.