You're describing an existing plugin called SponsorBlock.
IIRC it even has lots of options such as enabling you to allow/disallow self-sponsor segments (the creator promoting their own product), "like and subscribe" calls to action, shock-and-awe intros, podcast recaps, and several other segment types.
IIRC it even has lots of options such as enabling you to allow/disallow self-sponsor segments (the creator promoting their own product), "like and subscribe" calls to action, shock-and-awe intros, podcast recaps, and several other segment types.