You've not really stated why it would be useful, or when or how it would be used.
Useless comments can already be dealt with, so I presume your idea is for comments which specifically are "useful for a given time period".
Either to everyone, or a specific user.
Three scenarios - A comment is:
- Useful indefinitely
- Useful temporarily
- Not useful at all
Your proposal is no use for 1 as they should remain, and 3 as we have flags to remove those already.
However, for (2) I'm struggling to come up with a scenario or problem where we need some kind of function to assist or resolve.
What makes a comment have a finite time of being useful?
When to delete
You need some way to identify when a comment has stopped being useful and can be deleted.
Otherwise, with just your "insta-delete" keyword, there's nothing stopping the comment being deleted after seconds, or a few mins.
Who benefits from it then?
I have no idea how you would identify when to delete with accuracy or where it's useful.
Or how you would signal this within the comment so other users knew.
- How do we identify when a comment is eligible for deletion
- Who can delete it
- What determines a comment only has a finite usefulness
- Why would users use this to have their comment deleted? Users who
post barely useful comments are not likely to bother using this so
we can clean them up - comes with the mentality etc
- Why would users delete them? Most community clean up actions reward
users, or are substantially more useful than comment clean up
I'm not sure you could manage this problem successfully and realistically with a good ROI, especially given we are talking about "comments" which are "useful but not essential".
And for the most part, any suggestions for new functionality to comments tends to not be welcomed or cared about.
I'm still not even sure what you proposal aims to help with or resolve. Perhaps update your question with more of your thoughts? :)