https://webmasters.stackexchange.com/questions/95614/do-ad-impressions-count-if-the-user-is-using-an-adblocker summarizes Google Ads’s documentation at https://support.google.com/admanager/answer/141811?hl=en (TL;DR: pay depends on whether a script/request attached to the ad element is performed).

It’s true that different adblockers do different things, but the most popular ones do block the requests too. One of the most popular arguments for adblocking is performance and bandwidth. If we only hid the ad from view without doing that, we would not get the performance and bandwidth savings that adblock brings. So, µBO blocks the requests.

You can confirm yourself whether the request is blocked by searching “ad” (or “doubleclick” specifically for DoubleClick Ads, which are the majority of Google Ads) in your browser DevTools’s “Network” tab. Compare when the adblocker is off vs. on; for me with µBO the majority of requests aren’t even attempted and disappear when their entire element is ad-blocked, and in these cases the pay script doesn’t load either. The screenshot above only shows some requests that were attempted and blocked.

Going down the rabbit hole, doesn’t that then also imply that people using assistive technologies like a screen reader for the visually impaired are actually stealing content?

No, screen readers would still read ads. Just having the screenreader move to the next element is the same as scrolling past the ad. The difference is that if the advertiser doesn’t give alt-text, the content can become nonsensical. But the advertiser still pays.

You can approximately check an ad’s text for a screenreader with Firefox DevTools’s “Inspect accessibility properties” feature.