Does anyone remember the Steam Controller? I feel like this was also an effort to consolidate between KB+M/gamepad. I never got one, so I’m not sure if it really worked… though I will say it sounds like it’d be annoying having to finangle a game with no controller support to work on a quasi-controller. I much prefer the way Steam bakes in support for different types of controllers (even if sometimes controller support on some games is still weird, wrong button glyphs and strange implementations of rumble).
I think my view aligns with BMO here. Generally, I start by going with whatever the developer recommends I play with and have faith in their vision, whether KB+M or controller, and from there adjust to what I personally find comfortable. I typically play adventure games, visual novels or FPS with KB+M (though honestly I feel the lattermost gives controller support a lot more attention nowadays). Anything that I play that has the notice “Hey! Use a controller!” I’ll use that instead.