@florian
Not surprising that DNS-over-HTTP-over-TLS-over-TCP is a resource consumption worry compared to completely state-less DNS-over-UDP... what about DNSCrypt?
Also for ROOT servers, it does not make sense to encrypt if you can avoid sending full query as per QNAME Minimisation and if your use shared recursive resolver. Stub resolvers (you) are as anonymous as in case of use of VPN or Tor, no?