What does this mean?

Wisdom comes with age, so as you grow you obtain wisdom but you have to go through the trials and tribulations to get that wisdom, right? The more knowledge, the more grief - which like like saying ignorance is bliss - if you don't know about something, you don't worry about it. But when you know about something, it plagues your mind.

The more you understand the failures of humanity, how life is merely history repeating itself over and over, and the more you know, you understand more.
You witness more pain, in others, and yourself.
So, you have more sorrow.

It means ignorance is bliss

The more intelligent people are, the less joy they tend to find on the world. There is no magic left, because they know how it's done. They tend to see the bigger picture and see things as they truly are, rather than only what they want to see.

Lies are comforting, the truth hurts.

As I age I feel wiser but I also feel more disappointed with all of the negativity that people create purposefully. Doesn't anyone want to leave the world better than they found it?

the inverse way of saying ignorance is bliss.

which opens up all sorts of implications if you think on it too much.

It means the more you know, the more clearly you can see the tragedies in life. My opinion.

The more you know, the more you realize that deep down, people suck.

It means , that understanding doesn't bring relief, it only brings more questions, and more burden.

Think of children , and how easily they accept and move on.

Think of adults and how we obsess and regret.

Knowledge may be make you understand, but sometimes, that just makes it harder .

Might mean, the more you understand and know, the more you realise how messed up the world is which can be depressing. The flip side: ignorance is bliss.

No idea but here's a good resource I like to use

https://www.gotquestions.org/

Why ignorance is bliss. My path

Ignorance is bliss ?