A Netflix documentary on a largely-forgotten sculptor and artist from the early 20th C. I've seen a few of his pieces in underground comics and books, and had heard his Yeti conspiracy in SubGenius tracts but hadn't connected them previously. This film takes as primary source his bragging which exaggerates his influence, which in reality largely ended in WWII.
George DiCaprio, Leonardo's father, knew him, and both do narration and interviews and are making this film public on Netflix. So, take a vanity project for what it is.
His temper tantrums at museums and galleries are part of why he is "lost", but his really noxious antisemitism and Polish nationalism are the "we don't want you here" part. Like many European and English writers and artists of the time, even those who were in different countries and didn't like Hitler, he still loved fascism and inciting murder of Jews. He wasn't just obscure because he lost his Polish studio, but because he made himself untouchable. The film keeps touching on that and then startling away, and making apologies for him.
His later derangement and conspiracy theories of a deluge and Yeti-people are… well, charming by comparison, but claiming that many people right among us are subhuman corrupters isn't any better, and leads to the same atrocities if you get enough crazy people, and we're full up on crazy people these days. While the film spends some time on it, reading about his views online shows they really soft-pedalled it in the film.
At first I felt this was a bit of an American Movie clone, Stas' focused but low-class craziness and the long downward slide. But no, it turns out he's a very different kind of monster turned failure.