There is no clear evidence that the ozone layer is monotonically disappearing. Sometimes the hole is larger than others, and we believe the Kyoto protocol (banning CFCs) limited the damage we were doing to the ozone layer. Eventually those CFCs will leave the tropopause, but there will still be an ozone hole. In the winter at the poles, there is little UV to make new ozone. So if there is any water vapor, ozone will be naturally depleted.