When voting on the Low Quality Queue, you can see this deletion reason::
This is more of a reason suited to Stack Overflow. Perhaps we could change it?
I'd say we do not need this case. I mean come on, how often does it happen someone posts their own code for review into an answer?
This isn't even remotely enough often as that such a thing would make sense...
Looking at the recent deletions in the 10k tools, the only answers deleted were deleted by mods. I didn't check, (because the UI makes it kinda hard), but I think none of these deletions were for this specific problem.
I guess that most of this is converting to comments and cleaning up code-only answers, but maybe a mod can provide numbers on this.
Don't try to optimize things that happen once every leap year :)