I'm also worried about this, but also fear datamining by my ISP. So I
completely ditched Google, and split my queries between Cloudflare and
Quad9 - neither gets the complete picture.
I simply don't get how this is a use case for DoT or DoH. Even if you disguise the DNS lookup, the next packet you send will be directed to the address you just looked up. Unless this happens to be a virtual hosting service, it is quite clear to your ISP what you are doing. I recommend this talk by Paul Vixie
The TLDR is at about 33 minutes into the talk.