I think the biggest barrier to IPv6 adoption is that this is just categorically untrue and people keep insisting that it isn't, reducing the chance that I'd make conscious efforts to try to grok it.

I've had dozens of weird network issues in the last few years that have all been solved by simply turning off IPv6. From hosts taking 20 seconds to respond, to things not connecting 40% of the time, DHCP leases not working, devices not able to find the printer on the network, everything simply works better on IPv4, and I don't think it's just me. I don't think these sort of issues should be happening for a protocol that has had 30 years to mature. At a certain point we have to look and wonder if the design itself is just too complicated and contributes to its own failure to thrive, instead of blaming lazy humans.

For me just disabling IPv6 has given the biggest payoff. Life is too short to waste time debugging obscure IPv6 problems that still routinely pop up after over 30 years of development.

Ever since OpenVPN silently routed IPv6 over clearnet I've just disabled it whenever I can.

Now I'm sure I can fix DNSmasq to do something sensible here, but the defaults didn't even break - they worked in the most annoying way possible where had I just disabled IPv6 that would've fixed the entire problem right away.

Dual stack has some incredibly stupid defaults.