I do trust Quad9. I don't believe DoT is any more "battle-tested" than DNSCrypt, and DoT can be blocked just as easy. While DNSCrypt is my preference and recommendation I'd rather someone run DoT or DoH rather than nothing.Do you trust the person that runs the relay not to keep logs?
Like I said, there's no valid reason to run DNSCrypt when DoT is present.
If one is going down the dark web, it's a good way to get attention, and like I mentioned, even with a proxy, DNSCrypt is easily detected and defeated. Same goes with Tor...