Another thing to consider is that people can rate the raters. The information is bidirectional. (Like, on AirBnB, people who have left others bad ratings are more likely to be turned down by the next place. Or an author that leaves bad reviews on other people's books opens himself up to having them leave bad reviews on his books. Someone who rates products as sub-4 might find that other companies send him out-of-stock notices, instead of sale confirmations.) And this bidirectionality would be even more leveraged, on Nostr, as it would hurt your overall WoT score and follow you around.

That means there's a natural disincentive to give bad ratings, as they can boomerang, so you either need to be such a top expert, that you can afford to be critical (and hardly anyone is) or you only give good ratings or no ratings.