The text of the "not constructive" close reason reads:
This question is not a good fit to our Q&A format. We expect answers to generally involve facts, references, or specific expertise; this question will likely solicit opinion, debate, arguments, polling, or extended discussion.
But discussion is on-topic for meta (isn't it?)! discussion is one of the your-question-must-have-one-of-this-set tags! There aren't necessarily any 'facts' or 'specific expertise' about what's talked about in meta questions. Meta wants "opinion, debate, arguments"
And so on.
So I would suggest that this close reason is out of place for meta; at the very least, it needs its text changed.