I think that might be overestimating the technical prowess of HN readers on the whole. Sure, it doesn't require wizardry to set up e.g. Unbound as a catch-all DoT forwarder, but it's not the click'n'play most people require. It should be compared to just changing the system resolvers to dns0, Quad9 etc.

Running your own and being the sole user is the exact same thing as using a dns server (you need to obtain nameservers for any given domain which you have to contact a dns server for).

Except that your queries are spread out to different places instead of all being sent to a single server.

You ask .com resolver for domain.com's NS, and then you ask ns1.domain.com for foo.domain.com. Then you browse to wikipedia.org, and none of those DNS queries go to the same place as the previous site.

That's arguably worse since you are now in direct contact with the nameservers (which are usually managed by non privacy orientated providers).

One issue here is that you can be tracked easily.