Roblox is in a class of its own compared to fortnite and minecraft in terms of toxic monetisation.
Online gaming is definitely a tough one to navigate though, regardless. I had no problems as subscription was the limit to paying when I was a kid, but now it's a generation raised with mtx.
Servers can be bad, but that is entirely optional. Not even close to Roblox or Fortnite.
This is coming from a person that basically grew up with it from the Alpha stage.
It's certainly some of those things!
DLC tied to 3rd party IP (bonus advertising!):
https://www.minecraft.net/en-us/article/batman-dlc-swoops-mi...
https://www.eurogamer.net/dungeons-dragons-dlc-heading-to-mi...
Limited time events with exclusive content to make kids feel like shit if they don't/can't login at certain dates/times:
https://www.minecraft.net/en-us/article/discover-summer-cele...
https://www.minecraft.net/en-us/article/star-wars-celebratio...
In-game ads:
https://www.blockchaingamer.biz/news/16967/relentlo-brings-i...
It's unclear to me if any of their events or DLC includes loot boxes (mere chances to acquire certain content) or not. if they haven't done that, I give them credit
I'm also not sure how much direct advertising Microsoft does in-game. Have they worked with ad companies like this to promote third party or non-game content? https://www.adweek.com/creativity/minecraft-built-a-colossal...
I'm sure it's not as bad as Roblox or Fortnite but Microsoft does not have clean hands here either.
You want to give the kids Java edition which has none of this crap.
If you know a place to get an offline installer that doesn't require an account though I'd love to give it a try and see how the Java edition holds up!
Now I know to be a bit more careful when recommending the game without specifying huh.
Buy your kids pay once games with no IAPs. Teach them to keep a wish list and wait for sales :)