Younger Dryas impact hypothesis

No.13486876 ViewReplyOriginalReport
Why is it still called "hypothesis" when there are impact evidence found e.g. in the Abu Hureyra region, dating 12.8ky? Also there's an depiction of a comet/asteroid impact at Göbekli Tepe as old as the evidence found at Abu Hureyra. These two sites are just 160 km apart.