Same goes for druids and insects. Blizzard seem to je expanding what druids are since BfA. First, we get first two druid races who are not originated in Cenarion Circle and for that reason, they have different forms, based on Drust and dinosaurs. With Ardenweald, we learned Nature is based on balace of Life and Death and both serve the Cycle. Both can be used. Kul Tirans do so. Concept of druids using Death is already here, and will be possibly expanded in future when Malfurion returns from Ardenweald.
Allied race forms are remodeled cat/bear forms, but visually, they are vastly different. These forms were accepted well and since that, people request more and more druid form variants or even more customizations. Legion was also good on this, as it brought numerous form skins through artifacts. There is still big request for more and more druid form skins.
I believe when Blizzard expand druid races, we might see additional changes how will druids work with their forms. In Shadowlands, chosing form was changed from glyphs to Barber shop, which opens a way more multiple options. Now with warlocks being opened to all races, they open imp customizations to Barber shop as well, which may expand to other lock pets in future too. Now, I would not be surprised if they decide to shake up things a bit and add new barbershop options for druid forms again.
I also don't really know why are you refusing to admit that the Insect theme is obviously present within Druid class. NPCs, several actual class abilities from past and present and even Hearthstone are all showing this. To fullfil the "evil druid" niche, it is way more easy to expand existing class with new customizations. I am not even talking about undeads only. They can just do so for everyone. And that would still be less work than making whole new class, which Blizzard admited is probably the greatest commitment they make.