Don't hate
I'm pretty sure this will become an object of fun, but it shouldn't. Whatever you think of the song in question, it's clear the kid loves it, and that he's having a lot of fun. And until it glitches and the sound and image go slightly out of synch, it's actually really impressive seeing him mimic everything so precisely.
You go, "Fat Dutch Kid". Sing your crazy little song.
You go, "Fat Dutch Kid". Sing your crazy little song.