Strangely enough, the crackpots seems to prefer vixra.org to publish their work. I've never seen something like "4D wormholes can cure cancer" in ArXiv

If you make a new account, you either have to get someone to vouch for you, or you have to wait arXiv mods to look carefully through your first few preprints. If you are found to post pseudoscience, overly fringe theories, etc., you'll get banned from arXiv; that's why alternative repositories like vixRa.org popped up.

But I know why you think this; when I first joined arXiv many years, there were no such checks in place, at least not that I can remember.