The question Most important results in 2023 has been posted to MO, and as in previous years, has had a mixed reception. (EDIT: As of this writing, the post has been deleted by the author, presumably because of some negative reactions. It has since been reposted by someone else.) Whether such a question is appropriate for MO or not looks to be a recurring issue, and I don't think it has been discussed here on meta before. So, is it appropriate?
The main argument in favor, I think, is that despite some opposition, the analogous question in previous years has overall been received positively, and has received interesting and useful answers. (EDIT: See Noteworthy achievements in and around 2010? and Breakthroughs in mathematics in 2021 and Most important results in 2022 )
An argument against is that it is opinion-based in a bad way, deeming some results "important" and (implicitly, by omission) other results as "unimportant," not only in a narrow subfield, but across all areas of mathematics.
EDIT: Another view may be that the question is okay, but only if rephrased in a way that is less contentious; e.g., "Notable results of 2023."
I don't know if any kind of consensus can be reached here on meta, but it seems worth having a discussion about it that we can point to when the subject comes up again.
EDIT: Quanta Magazine has just published an article ("the biggest discoveries") and a video (the "biggest breakthroughs") in math of the year. One could argue that Quanta Magazine scratches the itch of those wanting to see such a list, and therefore there is no need for MO to duplicate the list. But another possibility is that the MO question could be changed to, "What results did Quanta miss?"