As someone who loves long, mellow rides on my mountain bike, I'm conflicted about Wilderness areas. I like the idea of protecting more land, but the idea that you can ride horses into a Wilderness area, shoot an elk and pack it out, but can't push a stroller in (because wheels) or ride a bike seems kind of odd in terms of the impactfulness of those activities.
I'd love it if things were mostly left up to local decision makers. Some trails aren't appropriate for bikes and that's fine, Wilderness area or no. Some trails within Wilderness areas would be no problem at all for bikes.
And tactically, maybe environmentalists would gain some allies if they weren't trying to push cyclists out.