Many people I know have bought more games on Steam than they could ever play (a behaviour encouraged by seasonal Steam sales). This strikes me as a great chance for people to discover and play titles that have sat in their collections for years.
I know I can get it to work, but when I'm at the point in the day where I just want to play a game for an hour before bed, the PS4 can have me into it in 10 seconds or less with a very low likelihood of drama.
Anyway, I know this isn't universal, but it's enough of a thing for me that I've even re-bought Humble Bundle games on PSN just so I can enjoy playing them that way.
Maybe Steam Deck would be polished enough to change my mind?