Yes, yours and the others I linked to were I think the ones that set the algorithm off. I'd been suggested them under the 'selcted for you' or 'from your network', liked them, commented on them. And then as I say, the Medium brain decided 'all he wants is to read about Barbie!' and my feed was filled with reviews of the movie for a couple of days.

I was reflecting the other day in another comment thread on music recommendation algorithms, which tend to be pretty good, given the inherently mathematical nature of music. But do they end up recommending satanic death metal to people who listen to Christian metal, just because the underlying music is the same?