OMG indeed! Have watched the previous match on agadmator's channel.
Proving now that Niemann cheated is nigh impossible, proving that he didn't cheat is theoretically impossible.
So it's up to your belief, intuition or who you like. (I"m on Magnus's side).
Except for that ending slide in the clip you attached. If D. Rensch of chess.com has evidence showing what he hints at, i.e.. That N. cheated more frequently and also when playing for money, he should show it. If it's true I fear people will have to accept the guy is a serial cheater.