It's an interesting situation. It is caused by the Apple TV being set to
match frame rate and the videos having different frame rates from the ads / UI. This means when the TV detects a different frame rate, it has to switch over to the new one which is that 1-2 second black screen with no sound. The only ways I see this of being fixed are
- Turn off Match frame rate
- Apple enables the HDMI 2.1 feature QMS. This might not be possible and require a new Apple TV model and in any case will require a TV supporting it (likely an "HDMI 2.1" TV)
- YouTube plays adverts at frame rates to match the video content to prevent the switching (either by having different versions of the ads or converting on-the-fly
YouTube are unlikely to do anything unless their advertisers complain, which to be fair they should: if you've paid Google for a 6 second advert but people only see 2-3 seconds that's not great. On the flip side, if this only affects Apple TV viewers (a niche) who have
Match frame rate turned on (smaller niche), advertisers are unlikely to find out...