As the title says, what are the risks, I assume people don’t host these servers for no reason. Is it just the ad revenue they get from the popups when trying to start the movie.
Could they be running exploits on here that would make it not safe at all to do so?
If you use safari content blockers combined with a DNS blocker configuration to block ads and malware, you should be fine. A lot of those sites will break though, compared to viewing them on desktop FF with uBO.