I’m trying to imagine how this would work in the real world. Are we supposed to have the entire population taking it daily on the off chance they might get Covid, or are we supposed to start taking it every time we come down with a sniffle?

Bret Weinstein, one of the most high profile advocates, thinks people should be taking it every day.

That does sound like he has stock options. Not even malaria medication is taken daily in the most affected regions, except for a few western tourists.

But... If the vaccine hasa lower risk of side effects than this does, which it appears to, and only takes two doses, instead of having to take it daily forever, why wouldn't we just get the vaccine instead? I suppose the use case is countries that are too poor to afford the vaccine?

AZ costs about $2 per dose. There's no way that giving ivermectin indefinitely is cheaper than that.

He thinks it has a higher risk of long term side effects. It's nearing anti-vax territory although he does admit the efficacy of vaccines and doesn't overplay the current knowledge on side effects. It's the boogeyman of possible future side effects associated with spike proteins that he's playing into. He thinks continued use of ivermectin is safer than vax plus boosters. And he thinks they're of similar efficacy so he's choosing ivermectin.