I repeatedly brought up all of these points here on HN when DoH was being developed. I suggested the developers of DoH reconsider the implementation and provide mechanisms for companies to manage this rather than bolting things on after the fact, which Mozilla have done. People only think about web browsers, but the internet is much more than that. API libraries must be considered, among many other ways that DNS is used inside a company between servers talking to servers, clients to servers, corporate VPN's, internal DNS names that may in some cases overlap with external and so many other cases. I still consider this to be a race for CDN's to centralize the monitoring of user behavior in the name of faux privacy. Like so many things, this was a good idea implemented poorly, in my humble opinion. The internet is not just Alice sitting at home browsing Youtube. Today, more than ever, people are having to work from home and DNS needs to work in a reliable and predictable manor.
DoH also prevents my hosts file to be used, with Firefox on Ubuntu 20.04.
Without DoH, Firefox filters ad-networks and other content I don't want to see, so I have learned to never use DoH unless I want to see all the ads again.