I heard this was a double blind placebo controlled study of the efficaciousness of Fenbendazole. . . Oh, sorry that's out of patent. My bad.

I run Linux Mint at home, where I also use Firefox. I've been with Firefox since forever. But when I run Windows - I generally end up using Edge. Why - two reasons: 1) Windows is for work, and the browser used for most of my work applications is Edge. 2) Firefox on Linux seems to me to be a much better product. Where on Windows the interface has changed and become Chromeless and free of menu's - on Linux it has stayed the same. I don't understand why the menu's have been removed. To me it seems like a silly default. They are useful to new users, who don't know how to restore them. If you don't want them - it would be easy to include a menu option to turn them off rather than change the defaults for everyone. Just my 2c.

This is important for GM because of the right to repair loophole for Wireless technologies.

Ultimately this is about trust. Do I trust my ISP or do I trust Google and Mozilla more. I can usually move to another ISP if I'm unhappy with them. My ISP probably has less commercial incentive to use my browsing habits to track me or sent me ads.

DoH does not tangibly affect the ability of my ISP to affect tracking. The route my traffic, so they know the IP's I visit, and with pretty high confidence can map them to where I've been going anyway.
Just because you can send traffic encrypted through https - does not make it a sensible thing to do so. Most small corporates use DNS reputation as part of their malware solution. Fewer SSL intercept all traffic. If all of a sudden they cant do that - they will buy a product to SSL intercept and do the same thing - but expose more of your web traffic to privacy issues at the same time.
If you really want privacy - get a VPN. DoH is change for change sake and not a good idea. I'm not saying Comcast or other are necessarily working in your best interests, but they are right on this one.