the ozone layer could be a problem again in the future if old appliances that contain cfcs aren't handled carefully when disposed of...

https://acp.copernicus.org/articles/25/11469/2025/

or if people start emitting cfcs again...

https://www.rnz.co.nz/news/world/487308/these-five-ozone-depleting-cfcs-have-been-increasing-in-the-atmosphere