Blocking isn't the issue, it's the websites that straight up break that are the hard part.

For example, Shopify hates ublock and will sometimes not load apps at all

DNS level ad-blocking usually doesn't break websites. (I use NextDNS)

The ad domains straight up don't resolve at all and never get loaded. I don't have any adblock/ublock, so the websites almost never could detect if I block ads or not.