Maintenance of “safety needs” is part and parcel of finding love and belonging in the first place. If we’re offloading that all together, then yeah I can see how more and more get depressed and suicidal. They don’t have anything to live for when you get down to it.
Moving up means those needs are being met satisfactorily and can be maintained without prolonged attention. And if a lower level stops being met, your level will fall to that level until it is met again.
I.e., if you're hungry and don't know when your next meal is, then who the hell cares if you're anxious, angry, or happy? You have more pressing concerns.
But it’s useful and, in my opinion, captures the most basic relationship which is that some needs have higher priority than others and will drive those other needs to the recesses.
What about that do you disagree with?
For the first time in history there is psychological space to care about mental health and social issues en mass. So, of course, there's going to be an explosion of diagnosis.