It's a tough question, I would be fine with ads if they were relevant to the content I'm looking at, minimal (ie; no motion, popups, covering up content), actually checked for safety so all the scam and phishing ads went away, and checked for performance so they didn't slow down a website so it's barely usable.

Maybe if adblockers become more widespread that will start to happen, right now ad networks seem to just allow anything.

Like if I'm reading a cooking article and there's an add to the side for some cooking gadgets or something like that, sure why not!