Ironically, I've seen people, particularly on Rosetwitter, who have rejected Corbyn as not being "true left" because despite Bernie going to England and talking to people about the election, he didn't endorse Corbyn.
They somehow didn't realize that Bernie was there to support his brother - which is a nice thing to do - and his brother is running for the Greens, therefore endorsing their competition would be a pretty stupid thing to do. (Despite the endorsement, Larry Sanders came fourth, and failed to secure the 5% of the vote needed to avoid his campaign deposit being forfeited to the Queen. A pattern that seems to follow pretty well with the candidates Bernie endorses in US politics.)
He most likely wouldn't have, and would have lost by an even larger margin. Just for one, his best strategy to date has been to appeal to the white working class, and that doesn't work for left-wing candidates in general elections, because the WWC hasn't broken Dem for about 50 fucking years. He sucks so, so bad at getting the POC vote, and those votes are crucial in the General. He might have managed to pull some white moderates, but pulling some of the white moderates doesn't win elections, and his message - especially his "Fuck identity politics, it's all about class warfare" message - simply doesn't resonate with POC enough to secure him the votes.
And yeah, people can bring up the whole PR angle that he was supposedly some hero of the civil rights movement, but as we saw in the primaries, that doesn't actually work - It sure as hell works on white folk who want to pat themselves on the back, but it only alienates the POC who know damned well that he wasn't.
Jesus, what a mad bastard. He's not the first person I've seen with those views, but he's one of the rarer few with all of those views simultaneously, that have actually left the US.