Which multiplayer games have the largest active player base?

I’m looking for team based games with an active player base. A lot of the multiplayer games available on Steam are dead but I’m craving an experience where you have to work together & communicate.

I’m not interested in VRChat or Population One, but anything else is fair game. I like shooters as a whole but I’m not limited to just that genre.

I’m also not really interested in 1-on-1 games like Eleven Table Tennis or Walkabout Mini Golf, I’m more so looking to play with a group of people.