This is Steam`s top 10 and 6 of them are free to play.
Counter-Strike 2 Free To Play 1,312,422 Players atm - Bot / Cheat infested and littered with kids
Dota 2 Free To Play 735,880 Players atm - Bot / Cheat infested and littered with kids
PUBG: BATTLEGROUNDS Free To Play 567,537 Players atm - Bot / Cheat infested and littered with kids
Team Fortress 2 Free To Play 154,147 Players atm - Bot / Cheat infested and littered with kids
Apex Legends™ Free To Play 1323,845 Players atm - Bot / Cheat infested and littered with kids
Call of Duty Free To Play (Demo) 123.218 Players atm - Bot / Cheat infested and littered with kids
There is a reason the 3`rd biggest tread on Steam Discussions are VAC bans ...
Yes the player count goes up, but it does so at the expanse of something else. There is no such thing as a free lunch, you get what you pay for.