Well… tris basically without limit is of course a huge benefit - both from a development time (no more LODs! No more baking normal maps!) and a result (endless detail!) perspective.
So yes, it’s worth it. But the requirments for Nanite are such that there is a lower bound on the platforms you can use and/or you may need to make some other sacrifices (like less moveable lights) to reach your minimum FPS.
For us, forward shading was always a last resort for our projects. But it still kinda sucks not to have it as an option. In a way, the downside with switching is that you’re not going to do all the LODs/baking anymore, creating a huge barrier for moving back to regular meshes (a huge barrier created by the work that you haven’t done, that is ;)).