That would work against them because you exclude the segments served up the least, and those modified versions would only be served up once. That approach could

That would work against them because you exclude the segments served up the least, and those modified versions would only be served up once. That approach could work better for YouTube if you did it to the segments of the actual video rather than the ads. But then you could get into things like audio fingerprinting of the segments - only show fingerprints that were also shown to YouTube Premium members. I'm no expert at this stuff, but people who build blockers will brainstorm every time they have to sit through a YouTube ad.