I've done a bit of peeking around and I am interested in making my own roblox game, it seems a good platform to get started on publicity-wise. Although I hear roblox takes most of the cut of profits you make from it as a game dev on their platform, its not really the money I'm after. I'm a creative that wants to make things that I like and that I think other people will enjoy too and garner a community that shares that same interest.
Personally I think there are some great gems to be found on roblox. I think Doors is a great experience for horror fans, Dragon Adventures is great for pet sim breeding games similar to Flight Rising, and Creatures of Sonaria is a creature survival game like The Isle or Path of Titans but with a made-up fantasy creature twist.
But I would agree that having your kid on roblox would take some monitoring. Their moderation is very lackluster and it can be dangerous if a child clicks on a suspicious link or suspicious game that could do malicious things to their account once in the instance.