Many don't, maybe most. It was when Sally Struthers was selling poverty and sympathy and we were constantly told about all the folks starving in America (by which they meant the U.S.A). Turns out much of that wasn't true and as the truth leaked out, folks might not be getting three squares but they weren't dying of starvation, the message changed to "food insecurity" where it has remained, though the meaning has become malleable. Malleability was key because as greater truths appeared the meaning was modified to suit the agenda and its narrative. Easy Peasy.
The 1970's were also the time of climate alarmists who were able to commandeer headlines and front pages of major magazines. With that much runway, and cautioning from experts who at that time were respected, one might think something would have been done. You might even point to CFC bans and reduction of the ozone holes. But the real problem is that these alarmists were warning of a coming ice age. This is despite the fact that other experts correctly pointed out that we were still in the current ice age. And it was coming to a close. Since then there has been a "expert 180". A pivot to global warming. After a few harsh winters where folks were freezing their collective arses off and paying mightily on global warming causing fossil fuels to boot, the "message" got lost. So we got an upgrade to climate change. This predated full control of media channels so legitimate voices pointed out that the climate has always been changing and would continue to do so. This forced a side step to climate change caused by human activity.
And that is where we are today.
The problem is that almost no one wants to do anything about it even though the answer is pretty obvious: reduce human activity. And the easiest way to do that is even more obvious.