I feel like Google has been cheeky for a while now in that they are either A) running ads off their own servers, same that show the video itself (so you can’t block the request without also blocking the video) or B) they’re hitting up their own DNS servers (ignoring system DNS settings) using DNS-over-HTTPS which you can’t necessarily block, and which could easily rotate IPs behind a reverse proxy. They could just pass the current IP in a response field from the initial HTTP request for the video and then use that IP to make whatever additional HTTP calls they need for the DNS records for the ad servers, bypassing PiHole or any other local DNS server entirely, since they could just open a connection directly with the IP (both for DNS and for content streams, ads or otherwise)

Because my PiHole (and/or AdGuardHome) seemed to work (or at least disrupt) everything except the YT app.

Now I have YT Premium anyway so it’s a non-issue for me as well. Makes me wonder how many other companies are going to do this and what can be done about it?