[stemlord]

This already exists on yt in the form of sponsored content in pro youtubers' videos, I use an extension called SponsorBlock that uses crowdsourced reporting to find and skip these portions... this crowdsourced approach will only work well for popular videos but unpopular vids are less often monetizable and thus not ad-ridden anyway

[ehsankia]

It also won't work for spliced ads that vary in length.