Out of curiosity I took the top most played games on Steam of 2022 as given here: https://store.steampowered.com/sale/BestOf2022?tab=3

Unfortunately it's not by hours but peak concurrent players. It's also pretty similar to the top grossing list. I checked each games Steam Deck rating and if it was verified or playable (usually means it needs text entry with a keyboard or doesn't support controllers) marked it as "works" (with the exception of TW: Warhammer III which is listed as not working because the performance isn't good on Steam Deck but it's a native linux title). If it was unsupported and the reason was given I marked as so, if it was some other reason I checked ProtonDB and noted the rating. I assumed if Valve marked it not supported it doesn't work regardless of ProtonDB rating (except again TW:Warhammer III). Out of the 90 titles there 21 are marked unsupported mainly because of anti-cheat or 23%, when weighted by player base that rises to 26%. So arguably it's 3/4 full. ;)

Of course if you demand every title MUST work and no alternatives will ever suffice I doubt you'll ever be satisfied. Anti cheat also gets rarer as you move away from big online games.

Here's the full list:

Over 240,000 Peak players:

Goose Goose Duck - works Ark Survival Evolved - works Elden Ring - Works Dota 2 - Works COD MWII (2022) - Doesn't work, anticheat PUBG Battlegrounds - Doesn't work, anticheat Yu-gi-oh Master Duel - Works Apex Legends - Works Lost Ark - Doesn't work, anticheat CS GO - Works Destiny II - Doesn't work, anticheat Dyling Light 2 - Works

Over 130,000 peak players:

Cyberpunk 2077 - Works New World - Works Monster Hunter Rise - Works Total War Warhammer III - Works WB Multiversus - Works V Rising - Works Path of Exile - Works Team Fortress II - Works Naraka: Bladepoint - Works Rust - Doesn't work, anticheat GTA 5 - Works Wallpaper Engine - Doesn't work? (is it really a game though?)

Over 75,000 Peak players: Raft The final chaper - Works Vampire Survivors - Works The Sims 4 - Works Rainbow Six Siege - Doesn't work, anticheat War Thunder - Works Fifa 23 - Doesn't work, anticheat Left 4 Dead 2 - Works Unturned - Works Witcher III - works The Forest - works Civ 6 - Works Valheim - Works Fifa 22 - works Football Manager 2023 - Works Dead by Daylight - Doesn't work, anticheat Dread Hunger - Maybe works? ProtonDB says Gold Warframe - works Terraria - works Football Manager 2022 - works NFS Heat - Works Warhammer Darktide - Maybe works? ProtonDB says Gold Warhammer Vermintide - doesn't work, anticheat Lego Star Wars Skywalker Saga - Works

Over 40,000 peak players Skyrim - Works Euro Truck Simulator 2 - Works Fall Guys - Doesn't work, anticheat Don't Starve Together - works God of War - Works Gundam Evolution - Doesn't work, anticheat Cycle Frontier - Doesn't work? ProtonDB gold Stray - Works Deep Rock Galactic - Works Stellaris - Works The Scroll of Taiwu - Works Mirror 2 Project X - Doesn't work?, ProtonDB silver Conan Exiles - Doesn't work, anticheat NBA 2K22 - Works Farming Sim 22 - works Marvel's Spiderman - Works Battlefield 1 - works Battlefield V - works Risk of Rain 2 - works Crusader Kings III - works No man's sky - works Final Fantasy XIV - works Red Dead Redemption II - works Warm Snow - works Mount and Blade II Bannerlord - works World of Tanks Blitz - Works Payday 2 - works Hearts of Iron IV - works Super People 2 - doesn't work, anticheat Stardew Valley - works 7 days to die - works phasmophobia - works VR chat - doesn't work? ProtonDB gold Undecember - works garry's mod - works Halo Infinite - works Stumble Guys - works Day Z - doesn't work? ProtonDB gold Mir4 - doesn't work? ProtonDB borked Project Zomboid - Works Cult of the Lamb - works Victoria 3 - Works Rimworld - works