It needed different details. In the reviewer's opinion the description included irrelevant details while omitting information which would be relevant to someone trying to decide whether or not to install the addon. Which is a perfectly reasonable assessment IMHO. A small amount of "flavor text" is fine, but the main purpose of the description is to ensure that prospective users can make an informed decision. Anything else can go in the app's "about" page or on a separate website.

Now if we could just get app stores to mandate useful changelogs… No, Google, "Bug fixes and performance improvements" doesn't cut it. Describe the bugs that were fixed and where and by how much the performance was improved. Justify spending the effort and risk of updating the software to the new version. There is no point in a changelog message that could be applied equally well to every release of every software product ever made.