Quote from edit questions and answers:
When should I edit posts?
Any time you feel you can make the post better, and are inclined to do so. Editing is encouraged!
Some common reasons to edit are:
- to clarify the meaning of a post without changing it
- to add related resources or hyperlinks
Therefor I think all such edits are appropriate.
If such edits are not appropriate, then I suggest some kinds of extra rules get implemented that one needs "enough rep" (whatever the amount) before being allowed to suggest edits to posts that are older than X days.
Note that if the OPers would respect the rules that they should amend their own questions to address comments to their questions, then such edits would not be needed ...
PS: Note that I intentionally skip all CLOSED questions (to avoid those would bump up as active again after such edits get approved).