Yes, he is popular. Yes, he loves click bait. No, he does not have a deep understanding of technical subject matter. All that said, as a journalist he seem to genuinely try hard to get to the bottom of technical issues relating to Apple and report on them.

"Journalist" might be a bit strong? He is clearly pretending to have a much deeper understanding of the subject than he does, meanwhile throwing around accusations of design flaws...

Bigger Cache would help GPU Apps which are not optimized for a tile based approach perform better. That this becomes a constraint on the Ultra and some apps some to suffer worse scaling on the Ultra the other products in the line seems reproducible though.