Ha! I kind of understand (apparently not really well from reading comments) CORS and many other web dev related constructs but oftentimes choose to work around them like what the zoom people did on the article exactly for this reason:

https://news.ycombinator.com/item?id=48616086

The whole thread shows that It seems even highly technical people that supposedly know a lot about this shit get it wrong. Because the mechanics are so complex, nobody really knows how they really work. Or it is a freaking mess or chore to achieve something.

Similar to just making a website HTTPS... even with let's encrypt and certbot , why does making a site https have to be so hard? (Try it on a service within a vpn).