I just noticed that the tag wiki for optimization says
While practical CharOp, solving specific build problems for a specific character in a specific game is encouraged here at RPG.SE, general theoretical optimization questions tend to be broad guessing games seeking things like "the best DPR." and usually are more suited to forum discussions.
(emphasis mine)
That's not been the trend lately, so I wonder if that text should be removed as contrary to community practice, or whether we've gone astray and it should be enforced.
Then
For context, that language was added April 7, 2012 by Brian Ballsun-Stanton after we ran into confusion over how the tag should be used. (See How should we improve character optimization question tagging?, dated April 6, 2012.) This comment exchange appears to the the genesis of Brian's tag-wiki edit. (This is in no way calling Brian out for this! Just laying out the tag's history.)
However, after the tag wiki was edited, we had another discussion in August 2012 about what kinds of charop questions were on-topic, since we were getting a lot of poor ones at the time. That original discussion is at Are character optimization questions on topic?
Notably, I don't find direct support for that added language in the two answers to that discussion. The closest is this in the highly-upvoted answer by wax eagle:
The last kind of question that I see as useful is the challenge question. These are the most borderline Op questions IMO, but they can also be the most fun. (Examples 1 2 3)
That "challenge question" obviously meaning theoretical charop, by context and the examples provided. In mild contradition of what was earlier edited into the tag wiki, this argues that they're very borderline in being on-topic, but are also the most fun (implying they're worth keeping more-or-less firmly on-topic).
Now
Given the recent concerns about the quality of our 5e questions, and given how much discussion theoretical charop questions have been needing in comments before they can be answered, we should be saying more clearly than this whether they're OK or not. To that end we should fix the tag wiki to match actual community practice and good site governance, whatever that is.
So are these on topic or off? Or are they somewhere in the middle, with some being off topic and some being on topic, and the difference turning on what point?