Ad blocker users say that they are seeing a black screen when trying to play a video on YouTube. Here's what happened.
Mashable reports that users ran into a black screen on YouTube, and that it stayed for about 6 seconds before the video began playing. The reports indicate it affected several browsers including Firefox, Edge, Vivaldi.
Some users joked that they would rather see a black screen than an ad. While that's certainly a better experience, it does waste precious seconds of our time. A simple workaround for the black screen on YouTube is to just refresh the page, hit F5 as soon as the page starts loading. uBlock Origin's filters were updated with a patch to resolve the problem, the add-on updates its filters automatically. If you are still experiencing the black screen issue, just open the extension's dashboard and manually update the filters. This tug-of-war is getting annoying, but it appears to me that Google's efforts are actively promoting the use of ad blockers, instead of attracting new subscribers.
I don't think DNS black holing was ever effective against YouTube ads. I use mullvad with a DNS filter for ads + uBO and still got served a few ad placeholders from YouTube in the past 10 days. I believe the actual ad was blocked by uBO, not the DNS filter.
You are correct. Google serves ads from the same domains as the actual legitimate content therefore sending those requests to null via DNS blackhole would simply block YouTube entirely. UBO and other browser extensions strip out or work around the problematic code itself to render a functioning page without the ads.