I run Zenarmor in addition to Adguard at home, which can detect DoH traffic and intercept it. You have to pay for this enterprise level tool, but if you are worried about DoH, Zenarmor is so far the easiest tool to block it.

In our house the only device that tries to use DoH is my partner's iPhone. It tries a few times, fails, then uses the Adguard DNS, which blocks the trackers.