So, like, yes Stephenson's metaverse is similar to a lot of video games we have now, but it's critically different because his characters are "heroes" in that universe specifically because they coded their own avatars and their own environments.
Which is another way of saying that it rewards thought, code, and creativity -- exactly the things that video games steal people away from.
If they want to meet with friends and hang around, real life contact just can't be beat. That's the reason why virtual persistent worlds are ultimately bullshit (as opposed to game worlds where you have an actual game to play, be that chess or matching colored gems or killing other players).
> You can code your own physical spaces and code your own avatar's abilities
I ask again: why can't I code my avatar to be the most OP avatar that ever exists? I will create a weapon that kills people if they look at me. What's the incentive to purchase new things if everyone can just code the most OP version and undercut the person next door? I will have the best cars, the funniest T-shirts, and the strongest potions, and you cannot stop me. Because I write Lua scripts.
There's some element of cooperation that is usually assumed when people talk about the metaverse but I don't see any incentive to maintain it that way. Garry's Mod and Roblox are platforms that do what you're talking about, today. The way they maintain this cooperation is that they prevent users from having strong autonomy in games that others make. In Roblox, your avatar is limited to a few cosmetic choices for customization, and in Garry's Mod, you don't really have any customization at all in most game modes.
So Second Life ...