Indeed, the fall of 4e and the rise of PF1 proved that “D&D” is more than just a brand name. But the rise of 5e and the fall of PF1 is proving that the brand name does contribute to what makes D&D, as do its proprietary settings and monsters.
The ongoing D&D traditions flourish. At the same time they include difficulties of various kinds.
The reason D&D 5e is ‘true’ D&D is because WotC made an extreme effort to find out what the D&D community wanted. WotC designers care about meeting the needs of players. WotC as a corporation made unprecedented outreaches to the D&D community, to discern the needs of D&D players.
Seeing 3e, I was so happy at the improvements since 1e. The systematization of AD&D rules was timely. WotC saved the D&D tradition. During 3e, I advocated nonvancian options, then delighted in the 3e (XPH) Psion. Also during 3e, I advocated passionately for balance, especially among player classes. Also balance among ability scores, each of which is a valid archetype to choose from. 4e gave balance, albeit a rigid form of balance. During 4e, I advocated that WotC always ask what the player base wants. Then I saw WotC reaching out to meet the needs of D&D players via attentive designers − and even corporate outreaches to survey what the majority of the D&D community wants − beyond my expectations, even beyond what I thought was plausible for a ‘corporation’ to do. WotC did amazing in regard to the surveys that resulted in D&D 5e.
WotC did so many things that I value. For examples, in 5e, the spontaneous Wizard and the full-caster Bard are two classes I advocated for, and I love the 5e versions of them. The 5e Bard is mythologically accurate (or at least mythologically respectful).
5e still has desiderata for me. I need to see monotheism be a *normal* option for progressive D&D (and animism and monism, and I appreciate spiritual diversity in general), and I need to see a Charisma elf that is inherently magic, preferably a sun-and-sky-dwelling elf (accurate to Norse world views) − even better this elf be psionic − and I want to see psionics in general that extends from a person’s own consciousness be a normative part of D&D.
Despite the fact that there are important aspects that I still need to see, I respect − value − appreciate − WotC and its designers make a remarkable effort to reach the D&D community as a whole.
D&D 5e puts me in a position where I have to admit D&D under the facility of WotC makes an honest effort to meet the desires of the majority of D&D players. For certain things (like non-vancian Wizards and full-caster Bards) I am happy to share among the majority. For certain other things (like monotheism, charismatic elf, and psionics) I seem to be in a minority. Even in those places where a minority, I suspect there is room enough in D&D for these options that I care about.
In all, I care about D&D reaching the player base. It has and it does.