All I see is a proxy service and a way for cloudflare to get access to the data
The DNS server sees (deciphers) the DNS query, but not the client IP address.
It's a proxy, but with the sensible data encrypted with the server's public keys to hide it from the proxy. Cloudflare never knows who is sending the requests. How can they get access to the data?
You can't tell how many people are going to be covered by that public key, but you could probably make educated guesses, or combine this with other metadata.
I'm not sure I see the point,tbh. If you want to control dns, why not resolve yourself, with whatever cache you need? And if you trust a company to do that for you - assuming the two companies do log "their half" - you're just a data breach, data broker agreement or an acquisition away from a commercial entity having all the data (again)?
I don’t know the answer but I’m curious to hear everyone’s thoughts. Personally I’d like to prevent Google and my ISPs but Cloudflare could easily become Google in many ways.