First they take the DNS queries. Then they start routing the rest of the traffic through their servers, while advertising how it's all "for your privacy and security", of course.
To be clear, I'm not against the principles behind DoH, and think traffic going from the local network into the Internet benefits from encryption; I'm against how it's being implemented at the application-level and its subversive nature.
That's fair enough, but in the short term, Cloudflare is more trustworthy (and tolerant of free speech!) than my ISP and government. Is there an initiative in which I have to trust none of these parties?
You can reroute DoH to your own resolver. If you have a trusted wildcard certificate on the device you want to reroute DoH for this will work 100% of the time. If you don't have a trusted wildcard cert on the device in question it usually will either not care or will fall back to unencrypted DNS.