Edit: no, I misunderstood, the location dot that's being displayed isn't the product of triangulation, they're just doing reverse geoip lookup. So, I wonder now if the edge network would perform better.
Update: it doesn't perform better. Either there is some kind of proxy redirecting their traffic or these servers aren't where they say they are, the center is skewed out completely. The universities win so far being correct and accurate most of the time.
Now yours consistently puts me somewhere into, or onto the shores of the Black Sea, while Vercels doesn't. So that makes me suspicious of your claim by using latency alone.
Edit: There seems to be outdated geo-ip information factored in somewhere. Why else it would put me IN the Black Sea?
Anyways, time to sleep. Sun's getting too bright.
This page contains websocket addresses of a CDN that returns ping pong from a huge number of locations. It works surprisingly well for working out very fine grain location in just playing with it.