I stalked my brother-in-law's Steam profile to judge him by the games he most played, and realized that other losers might be doing the same to me.
In order of most hours...
Warhammer: Total War Franchise with 1500 hours+ combined
and then a far far second place, like US military spending compared to others:
Elden Ring
Assassin's Creed Odyssey
X-Com: UFO Defense
X-Com: Enemy Unknown
Final Fantasy XV
Skyrim
Battlebit: Remastered
Battle Brothers
Battletech
Darkest Dungeon
Hades
Stardew Valley