In my own plugin dir pages when I get a notification of a comment, its usually spam. I send it to the moderator (Helen Foster).
In many cases though I doubt plugin admins are that active. I just came across a plugin with 12 pages of comments, almost entirely spam.
https://moodle.org/plugins/filter_simplespeak
Its not the fault of the plugin's author in my opinion. I just don't think we can expect plugin admins to all maintain their own comments. But I really think we should put in place some way of keeping spammers out , that does not tax Moodle's own human resources.
Do we even need comments? Could we just turn them off?
*EDIT* I had a look around and while there is def. spam on other plugin comments, nothing like this one. Perhaps its just an outlier?