If yes, why this is open?
If no, why this is closed?
In either case, why isn't it covered in FAQ?
The FAQ says:
Questions are acceptable as long as they require specific Drupal expertise to be answered. Does the answer change if you use WordPress instead of Drupal? The question is on-topic for Drupal Answers Stack Exchange.
That part of the FAQ has been added only after September, 2011 to make it clear that Drupal Answers is not a version of Stack Overflow where every question contains the word Drupal in its text. The reason the first question you link is still open is that was asked before the FAQ was edited, and nobody voted to close it.
The first question you linked could get an answer specific for Drupal, if there is an editor that allows to format the code following the Drupal coding standards. I don't find it particularly constructive, since everybody could suggest a different editor they are using. (If it didn't happen, it just because few users answered it.)
For the part about allowing to use different extensions, the second question you linked doesn't have an answer specific for Drupal and it can be easily answered by looking at the home page for ApiGen, as I linked in the comment I posted.
If you ask for a more complex setting to use when using ApiGen with Drupal, the question IMO would be more acceptable, and surely more interesting than a question asking which editors have a code formatter to use with Drupal. At least the topic would not be any editor supporting PHP for syntax highlighting / code formatting.