honestly surprised to see overwatch at the top of this list, but it's early yet. it's what i voted for since it's one of my favorite games of all time and definitely my top multiplayer game. thousands of hours in it and still playing regularly.
but while i am still enjoying the game, i do think there's so much more potential for it to be way bigger than it currently is given how absolutely massive it was on release and for its first year and a half. maybe it wouldn't have gotten any bigger than it did because the battle royale phenomenon was going to happen anyway, but there's a part of me that thinks in an alternate universe where blizzard handled it better, it would still be among the most popular multiplayer games to this day instead of languishing with a quiet and more-often-than-not frustrated userbase. it's certainly not a dead game by any means with millions still playing it monthly, but it's not exactly popping off on twitch/youtube or raking in the big bucks in esports.
i am optimistic though that if overwatch 2 does its pve content right, the big casual audience the first game attracted would be right back in it and the game would have better longevity among that crowd, which in turn would draw in the content creators and high-level players.
special shout-outs to apex legends. had a blast playing it for over a year, and even though it didn't turn out to be the "fortnite killer" that it was looking to be when it first dropped in terms of popularity, it's managed to carve out its own niche in the super competitive battle royale space. i can see myself jumping back in if it's true that overwatch 2 won't be out until much much later in 2022.