Ah, this is a hard one. For one part, yes, this is spam. For the other: What constitutes an advertisement? Do we really want to filter the summary on a low (i.e. non-user) level? This seems ... controversial.
I guess one could add the SponsorBlock Database (open source license), they have a database of all sponsored "spam" segments. (Even Intro/filler/outro/subscription reminder, etc). EVerything is categorised and one could filter out specific categories from the summary?
