I know it's the in-thing at the moment to shit on old Trek...
Whose shitting on old Trek?
The Wrath of Khan
and Star Trek Into Darkness
are two films separated by thirty-plus years and different audience expectations. I watched TWOK after the second time I saw STiD and it is still an incredibly entertaining film.
Either Nero was going to be captured or destroyed by Kirk. They weren't going to take a chance on him slipping through another black hole and causing more havoc elsewhere.