Well on console I had about 60 games (physical copies that made a huge tower on my desk) on my PS2 before I sold it. Funny story is that when I got rid of those games I received $2 per copy, resulting in a pretty shoddy $120 for all my prized possessions. I paid at least a quarter of that amount for a single game, definitely not a good ROI if you ask me. But at least I enjoyed the games.
On Steam I currently own a measly 6 games: Terraria, CS:GO, The Binding of Isaac: Rebirth + Afterbirth, Stardew Valley, DIRT Showdown and Insurgency. They suffice for my needs and you can play almost all of them for hundreds of hours without getting bored.
I should also add that I thoroughly enjoy playing games on my phone and I've accumulated a library of at least a hundred different games. I don't play 'em all of course and having them installed at the same time would be a headache, but they do all sit on my account, ready to be redownloaded at any time.