I was being too simplistic in my other reply. I was referring to basic router based DNS and NextDNS as the upstream resolver.

I don’t have an answer for hard coded DNS when it comes to NextDNS, which is essentially an upstream resolver with block lists functionality.

And to be honest, I misinterpreted OPs original question which was to take PiHole to the next level, whereas NextDNS is an alternative to.

I can run app based routing and blocking on my router, but whether that would restrict DNS for those services I don’t know.

Thanks for the clarification, you’ve got me wanting to pursue more DNS control now!