I gave an honest opinion: I said he needs to pracrice on his skills, that greebling would go a long way, etc... however I didnt make comments like these:
Long awaited by who?
MY EYES! THE GOGGLES, THEY DO NOTHING!!!
Honestly, this is worse than that cargo container I made!
I didnt see any constructiveness on them... as for the first quote: let him keep his illusions, he will naturally, eventually loose them

Its pretty simple, he will find out that if his stuff is sub-standard, people wont play it (which is bad for him). In the meanwhile, it is our task as a community to give our opinions (decent ones) on how he can make his stuff to standard level... politely, flame free.
In the eventuality that you are fed with his attitude, just say nothing at all

But honestly, flaming, being sarcastic or whatever, just gives us a bad name, which is negative in the long run