Is it really good to succeed at a young age?

I often met people with the mindset:

"I'll work hard until I'm 30, and then I'll enjoy the fruits of my labour."

Many people wanted to get into the Forbes 30 Under 30.

Now I see people around 18 who are already exiting their projects (in addition, they also have health problems because they didn't distribute their energy optimally), and the age limit is moving lower.

I remember the founder of Loom saying that he exited a project for a lot of money and doesn't know what to do with his life.

Is it really good to succeed as a young person?

Because if I look at it from a different perspective:

When you reach the top at a young age, what's next?