Lots of the key people working on things like SDL that Value very heavily relies on are also very vocal critics of the Steam Input API. Steam Input is a bastardization of SDL technically.

I have personally benefitted from the steam input feature in niche cases, but the way it hijacks everything by default even when not enabled does seem to be poor engineer-ship. I have run into some issues when doing controller management within games, only to realize it has to be solved at the steam level.