I think so. What a meaningless life not putting any value into ones own or others struggles. Met many older people who lack any form of humbleness, they always think in terms good/bad, friendly/evil, worthy/not worthy.

I meet wonderful people to, but every time I met a person who seems to learn nothing from life I start to doubt humanity.

Maybe you should doubt humanity...

That's my Mormon father. He learned nothing. How can I advance, knowing that Dad is a dirtbag? That's my burden. I am born of evil, Mormon evil.

wow... not my experience. I am continually learning. I love life, my New Normal as a widow living alone after 50 years of marriage.
I have a very supportive group of friends and relatives.
We have a lot of fun, laugh a lot, share experiences.
I'm often shocked by some people's inhumanity. But that's the exception.

A lot of therapists would be out of work.

My DH is a mental health counselor, and he just shakes his head when he sees clients jump like kangaroos from one horrible relationship to another. And they wonder why they are still miserable. . .

Lots of people learn from experience. The problem is they have to actually be willing to first, and many people aren't. Also, even when they are willing, it tends to happen more gradually than people would like, so it's hard to see the progress in real time.

A lot of people learn the wrong lessons from life. Like two people who go to jail- one gets out a better man willing to stay out of trouble, while the other becomes bitter and continues to get into trouble blaming all his woes on society.

Like the glass that is half empty or half full, people learn and live according to their perception of the glass. Life's lessons are then learned based upon either gratitude or jealousy.