This is his response. Totally deranged.
You know, if I didn't know who Shigeru Miyamoto was and saw Bob's tweet without context, I think I'd assume the Miyamoto was a revolutionary with a cult of personality who'd taken over some small island nation near the Philippines.
I'm no expert folklorist but as far as I can tell there's no part of that large tweet that Bob got right:
If you spell it "Yōkai" instead of "Youkai" you should probably at least attempt the macron over the O. (To hell with typing macrons, I'll use the alternate spelling.) Then again, maybe I'm just being a diacritic purist on this one.
Youkai aren't poltergeists. For one thing, a lot of them have physical bodies. Two random examples:
1) A kitsune is literally just a fox. Foxes in Japanese folklore have paranormal abilities and extremely long lives, the foxes you see are generally young ones who haven't come into most of their power yet.
2) Western vampires are sort of youkai: the Japanese term for them (not counting the transliterated English word) translates as "Blood-sucking oni" and oni are youkai. Not surprisingly I've seen the word used to mean "supernatural being", a two-syllable word that makes an elegant shorthand without the baggage of English words like "spooks" or "monsters".
Conversely, poltergeists are one specific kind of paranormal manifestation. Bob's pointing to anything with wheels on a highway and calling it a pickup truck.
Also, poltergeists don't need to be the ghosts of people. Hell's sake, some paranormal types figure they're not ghosts at all, they're uncontrolled telekinetic potential from one of the living members of the house. (If I recall correctly this angle was taken due to the number of poltergeist hauntings that had a pubescent teenager in residence, the implication being that the kids are inadvertently pulling a Carrie.)
I'm not sure there's even any Japanese equivalent to the poltergeist, not that equivalencies are easy at the best of times. For example, you could sort of make the argument that the Scottish brownie and the Japanese tsukumogami occupy the same "ecological niche" of a household spirit that can help or play pranks - or, if abused, turn downright malicious - and are therefore similar but the two creatures are so wildly different otherwise that there's no ground for comparison otherwise.
"Poltergeists" isn't a proper name. Neither is "animistic". They get lowercase letters.
Oh, and while Shinto is animistic and that does carry over to other elements of the culture, I wouldn't suggest telling a Buddhist that their "spiritual system" is animistic, capital A or not.