The nonstop warnings of the Ozone layer were probably among the reasons for the quite decisive switch away from CFCs, preventing the problem from getting truly bad. It's an interesting balance: you need to push it through to people that something needs to be taken care of, it's mostly successful and everyone is annoyed that it wasn't so bad after all, why the panic? (I wonder if Y2K is a good IT equivalent: Not much happened, because people were worried before and stuff got fixed, but the worry jumped over into mainstream not seeing that distinction)