The hope is that with smart switches, no one needs home assistant to work anything in the house either - they get a UI they have had their whole life, a simple switch or toggle button. The smart part is an optional extra guests don't have to worry about, they just use lights the way they've always used lights.

You can't control color easily, but you can get dimmable smart switches. I find for most lights, I don't change the colors pretty much ever. YMMV.