[charlus]

I followed your search instructions - and skimmed a few hundred of the 1 star reviews, the only 2 I could find that were positive are the ones you mentioned. So I'm not sure this is as much an issue as you indicate? That review saying "ADVERTISEMENT" is not because they are stating the review is an advert, it's because where they copy/pasted it from includes the alt text of an advert.

[nvm0n2]

Not sure. I noticed this problem weeks ago. Back then those two were the top results if you filtered for 1 star reviews, so it was really noticeable. I didn't do an in depth investigation though.