Why rely on third parties? Setting up your own recursive DoH server with the appropriate settings (PiHole etc) is super easy.

It's even free if you use the free forever VPS server Oracle will give you. The uplink being limited to 50mbps isn't an issue for DNS (and similar lightweight protocols).

I'd recommend putting the DNS behind a secret subdirectory though, because my server accidentally got added to a DNS server list and a small country started querying mine at about 30k per second