Don't discount multiplayer gaming as socialization with friends. My mother hated how much I was on the computer, but I had ample friendships and computer related hobbies and learning, and well my entire life is spent on a computer. That's just how some lives are nowadays.
If they are just queuing with randoms or spending all their time watching a stupid twitch streamer, that's not socialization though. I don't think you can actually form connections with other gamers anymore with the way modern matchmaking works.
There's something to be said about missing out on other dimensions of social life when socializing online. I would argue that it's not a substitute and poor preparation for the human condition.
If they are just queuing with randoms or spending all their time watching a stupid twitch streamer, that's not socialization though. I don't think you can actually form connections with other gamers anymore with the way modern matchmaking works.