This is just trolling. You can make your argument without resorting to this sort of childishness.
Neither insults nor trolling is childish. That is not a valid argument and has been used ad-nauseam against both. It's fun to read if you're in the right mood, especially when it is on-point like here.
In your opinion, which I'd question if you think phrases like "pasta fucking pizza wanking twat" and obscene 'your mom' jokes aren't immature dialogue. Hardly witty insults are they? Regardless of how fun you think it is, he's clearly doing it to agitate and it's unnecessary and derailing threads.