I'd love to have a Druid in a DS campaign. I'd love to have a character who I can describe the desiccated nature of the world to, the endless blackness they feel when near a defiler, etc.
I agree on the rest tho
Druids back I n2e did worship elemental spheres as well as the sphere of the cosmos. They did have the best spell selection but they could not wear any armor and were limited a bit with weapons if I remember correctly. A druid of fire is not diametrical to the (good) parties goals eventually, e.g. he just took up residence at lets say lava falls which create fertile earth and lands around it, so that is not a nature destroying class although by name it first may imply that. I see no problems at all to implement druids of any playable race into a 5e conversion of DS.