It was interesting hearing about Nathan Glass. However, now I'm curious about the types of all MBTI youtubers (some of which also discuss Socionics). I've listed some of them here. Feel free to add more if you desire.
Frank James:
I think he's IEI, so I think INFJ definitely works in terms of cognitive functions. His videos are entertaining, but they're not insightful enough to really grab my interest.
Casual Cognition:
Calypso:
I'm seeing Fe here, so maybe also IEI, but Fe subtype? Could also be IEE though. Those videos are very interesting lmao.
Alex:
She looks similar to some of the SLI girls I've known. I haven't looked too deeply into her yet, however, I've not really seeing any Ni so far.