As for the other questions, I don't see what they have in common.
What should be done with this tag?
I can't even explain why the tag exists at all, let alone what it might be supposed to mean.
I could hazard a guess that some people might feel that asking for an explanation of a preferred choice (as opposed to simply asking Should I use “such that,” “so that,” or “in a way that”?) might make a question more "On Topic" (i.e. - less a "matter of opinion").
But quite frankly, it seems to me about as useful as the tag for usage - I'd say get rid of both.
It got worse, there are now 35 questions tagged explanation.
We should really stop this tag in its tracks now.