Has anyone noticed emails in the Promotions tab of Gmail with a "carousel of images"?

The emails resemble Email Annotations rolled out from Google ~five years ago, but looking under the hood they don't appear to have annotations code.

Currently, there is documentation for a Deal Annotation and a Product Carousel. There is not a mention for the carousel.

It appears to be something Google is applying to some emails, but it's unclear what senders, what emails and why.

We deep dived on the topic if you want to read more, but curious if anyone else has noticed this?