This isn't the same thing. That's just a hard-wired DNS server, which can be easily forced to use your own servers at the firewall. GP is talking about DNS over HTTPS, which can't be fixed in this way.
I mean the game of controlling 3rd-party devices that we don’t really own via side channels is always gonna be a cat-and-mouse of ever more elaborate hacks.
The next game will probably be mitming these devices by flashing a new CA store.
There is no general solution to running an openly adversarial app/device in your network.