Looking at a query of all closed meta questions, it seems we've never used the opinion-based close reason on meta.
This site has been up for years, yet we've never found an "opinion-based" question in need of closing. So why don't we remove that option?
Can opinion based questions be posted on the meta? seemed to conclude that there are many opinion-based questions here, as a result of the discussion tag, but that off-topic questions absolutely still exist. It's not appropriate to close questions as opinion-based on this site.
It is ideal to justify claims in meta with reasoning, but having a discussion tag opens the flood gates per se. If we actually enforce the opinion-based close reason on here, we'll have significantly fewer questions! And that's why we've never enforced it. It's easiest to discuss ways to improve the site when opinions can be given.
I'm requesting a complete removal (if possible) of that reason to close meta questions.