There is an interesting guide (in French) on best-practices to get DoH up and running with dnsdist (https://dnsdist.org) here: https://www.bortzmeyer.org/doh-mon-resolveur.html.
You might also be interested in looking at https://dnsdist.org/guides/dns-over-https.html
I do want a container with my own DNS-over-HTTP running on my own hosted VM (or Digital Ocean, or Vultr or Linode or whoever) and I'll ship my DNS queries there.