I use my own public powerdns dnsdist and recurser/authoritave instances for DoH, DoT, DoQ, TCP and UDP now for ~3 years. Setup took some time, because i used bind, unbound and dnsmasq before. It's super stable and i can also use it on my mobile or legacy devices and as resolver in unbound, adguard/dnsproxy or just in my local resolve.conf.
If its public , how do you prevent others from accessing it?