I've never seen Vaporwave with dinosaurs or gross-out asthetic. Sam obviously is talking out of his ass doing the art/symbolism bit, but it's cringe and gay. Moreso that he uses it to give points to the wrong doodles.
My favourite part of that whole scene was when TTS said something like "LOL What would Goldstriker know about art?" and Sam gets obviously butthurt and snaps back "I know waaaaay more than you!" That's at around 11:50 in the video you posted.
It pains me to say it kiwis, but I think Sam is becoming the thing he always hated.