So I do wonder how such systems can be designed or implemented such that geoip systems can still work.

While I'm sure aws route53 and cloudflare's own routing systems can handle this properly, Cloud isn't quite the answer. Not every workload fits on the cloud (see: Discord, which runs on leased servers), and a system that breaks down if your rented datacenters aren't in alignment with Cloud operating regions doesn't make a great solution.