> I’m surprised home many technically knowledgeable people on Internet forums still think IPv6 is some niche, unreliable thing.

The more technically knowledgable you happen to be on the subject, the more you realize IPv6 is some unreliable thing when compared to IPv4. Perhaps no longer niche though.

It's unfortunately still an afterthought for many backbones - and not just US-centric ones. There is a noticeable difference in performance metrics from clients served via IPv4 endpoints vs. IPv6 for web assets in the same locations from the same transit providers.

It is pretty much the opposite of "just works" depending on your definition of "just works". It results in more Traffic Engineering per bit served by a large factor compared to IPv4.