I think we are seeing more mental health issues because people are recognizing it for what it is. Just like how you were able to see that he was having a panic attack and not a heart attack. Your response was to talk to him, not to take him to the ER. Perhaps even he himself was able to say, my body is fine, but my brain/soul is broken. It's unlikely that his father or grandfather would have been able to recognize that or even acknowledge it.
It bothers me when people call those who are able to identify their mental problems as weak. It is not weak to say "I have depression" or "I'm neurodivergent so I interact with the world differently" or "I'm grieving." In fact, quite the opposite. To be able to recognize and be self aware of your mental state takes incredible strength and even more to be able to overcome it.