Also, don't use Roblox, you can freely share games made with PICO-8, Löve, Godot, Rpgmaker, Game maker and the like, no need to go to the hell scape that is Roblox and its dark patern and locked down ecosystem.
I agree that Roblox is a hellscape when you want to make serious games, eg make money from it or sth, but if you just want to mess around making a “supermarket horror tower defense” game full of in-jokes and then have all five of your friends join it, and It Just Works, sorry but nothing comes close to Roblox.
Until they required age verification for that ofc.
Also, just don't ever buy any Robux and kids will auto steer away from the shitty games that need it. That filters out 95% of the badness of Roblox right out the gate.
Don't get me wrong. I agree roblox is a very shady operation, but that does not erase the fact that their platform is unmatched when it comes to letting kids make games.
There also Luanti, the new name of MineTest, which is closer to the Roblox experience (in the sense that there already a playable game there, and creating new stuff is closing to modding than to game making).