He is an entertainer, and he is entertaining. I don't think people are watching his channel to learn gun safety, but rather to be amused watching exotic weapons used in ways you won't see on the History channel.
Like him or not, one thing is for certain; he has made a name for himself, and amassed a decent fortune doing something fun. We should all be so lucky.
As for unsafe practices, well......he's not doing these stunts at a public range, so the only people who are in danger are willingly so. I have no problem with people engaging in perilous acts, so long as they do not endanger innocent people who have not consented to being put at risk. Kinda like seatbelt and helmet laws I so vehemently disagree with; it's my posterior and only mine, so why is it anyone else's concern how I do or don't protect it?