If your router can do it, have it route all of your DNS queries to your (pi-hole|adguard|nextdns). Doesn't matter if they are hardcoded to 8.8.8.8, anything to port 53 goes through the blocker.
Asus Merlin firmware handles this nicely.
Asus Merlin firmware handles this nicely.
The only downside of the XT12 is that there are no USB ports, so you cannot have external storage. Definitely WTF, but an OK trade-off for me.
My work systems bypass everything and I route them to Quad9. If that breaks my work stuff, then the IT department has some splainin to do.