These ads aren’t ads so much as previews for other Netflix options, and Netflix is currently only testing the new feature in limited markets, which explains why relatively few people have commented on Netflix ads as well as why the comments seem to come from people outside of the U.S. market.
If anything, this sounds similar to what users in non-U.S. markets reported with the rumored “Ultra” option for subscribing.
According to Netflix in a statement (via Cord Cutters News), the streaming service is “testing whether surfacing recommendations between episodes helps members discover stories they will enjoy faster,” and notes that users are “able to skip a video preview at anytime” if they’re not interested in what the footage shows.