Same thing with the hole in the Ozone layer. People think it was never a problem because we don't hear about it anymore, not realizing the issue has been mitigated and is recovering as we took concerted efforts to understand the cause and fix it before it became a disastrous situation.

Fun fact, pandemics can be addressed in a similar manner. With plenty of resources and scientific collaboration, potential pandemics can be identified, risks and remedies can be researched, and then policies can be put into place to prevent them from rising to the level of a pandemic in the first place. The problem is that people generally don't see that a pandemic was prevented, only when they fail to be prevented. Also preventing them takes money, and requires policies that can temporarily negatively affect economies. Those things are mortal sins to conservatives and libertarians. So they dismantle programs that already exist or cut their funding to make them as useless as they believe them to be. Then the worst happens and they get to point at the program that failed and use that to justify never spending money on it again. Yaaaaaaaaay!