> The question then becomes, whether Adblockers could use this information to skip the ads. It's a cat and mouse game.
I wouldn't call it a cat and mouse game because there is nothing from a technical point of view that prevents adblockers to use this information to skip ads. Unless YouTube gets completely rid of the concept of timestamps for their videos, they will always lose this battle.
They could make the timestamp conversion very Server-Side or create a very unwieldy API where it's difficult to collect all ad segments via timestamp sampling.
I wouldn't call it a cat and mouse game because there is nothing from a technical point of view that prevents adblockers to use this information to skip ads. Unless YouTube gets completely rid of the concept of timestamps for their videos, they will always lose this battle.