If the other kids are jumping off bridges, I would have a great reason to tie my kid to the house. But this isn't that obvious to kids. They will be resentful, they will hate your guts. This will have lasting consequences to your relationship
But they aren't jumping off bridges are they? They are all having a good time playing together on Roblox. Are you honestly saying that playing on Roblox is as bad as mass suicide?
Sure except none of them are playing minecraft so its not really the same thing.
Me siting down and explaining how government or corp. issued age verification is bad is really not going to make him feel better about sitting alone in his room night after night while all of his friends are online having a good time.