In reply to Serge.

My review did include a link to WP User Avatars on the repository, so if the moderator had said that was against the rules I’d be guilty as charged. But that’s not what the mod said, and I think the mod took a subjective and rather expansive view of what a “recommendation” is.

Actually, links are not allowed in reviews.
https://wordpress.org/support/forum-user-guide/faq/#why-are-links-not-allowed-in-reviews

However I can imagine that the wording of the moderator can be interpreted as unfriendly and off putting. I experienced this as well. I try to remind myself that these mods are doing this work voluntary (sometimes for years), see a lot of misbehaving and mostly mean well. It might be a professional bias or deformation. that lead to responses like these.