Roblox has a very good Lua ecosystem. It's on the scale of an actual featureful game engine now, with free cloud hosting and microtransactions support and developer payouts that attract would-be gamedevs. It's been growing extremely rapidly with players, and makes it very easy for kids to open up the game editor and start slapping blocks around to try and switch from "consumer" to "producer".

I'm 21. I first learned programming through Roblox when I was like 15. I don't play anymore, and haven't for years, but I have a giant friend group that also got introduced to programming through Roblox. A lot of them have gone on to work there now, and they've been making it better and better over the years.

Minecraft is giant, and there are tons of mods for it, but also the barrier to entry for making those mods is extremely high. You have to open a command line, decompile a jar and deobfuscate the bytecode and then use Java, which historically isn't the best first language to pick up for a kid. More kids have probably been introduced to coding through ComputerCraft than have gotten a mod building correctly.

They're more than just mods. Pretty much _every_ game in Roblox is built with LUA scripts. I'd go as far as to say that Roblox is more a game engine than it is a game.