Why do people use DoH?

  - they want DNS over TLS [multiple reasons why].
  - they want to work around "problems" in the architecture of DNS.
  - they want to force new functionality [read: protocol changes] on users without other DNS infrastructure adopting it.
  - they can.

Are there lots of problems with DoH? Yes. Are we ignoring them all so we can get the above? Yes.

If you love privacy more than freedom, DoH is great. If you want the internet (and local/private networks) not to resemble America Online, DoH should frighten you.