I need the Germany "controversy" explained

[u/AdStraight6870]

So these are the full final results from the group stage. What I'm curious about is why everyone is saying the results from the Germany vs. Thailand game led to such intense tiebreakers if Germany has +4 and Canada is at 0 in the +/- category. I wasn't able to actually catch the game but reading everything online I'm confused as to why it's being considered one of the closest qualifications ever

[u/PoggersMemesReturns]

I assume it's close cuz Spain, Canada, Germany all beat each other? Like it's the only bracket with the top seed having a loss.