Interesting read. Thanks.

I completely agree with you regarding "you must do you."

However...

As discovered by Angela Duckworth when she studied what characteristic best predicted success among West Point cadets, it was grit - defined as having courage and resolve - the ability to stick with things when the going got hard (https://angeladuckworth.com/grit-book/).

Grit (IMHO) is what separates people who do things because its fun in the moment, and those who do it because they see a greater purpose in doing it. That greater purpose can be altruistic or egocentric, but it's something that lets you keep going when others just give up.

When someone urges you to figure out your "why," it's intended to help you access your own intrinsic greater purpose that will let you keep going when your automatic thought is, "this isn't fun anymore."

My personal bottom line here is that pursuing your passion, purpose, "why'," or any other thing you may call it, helps you achieve bigger goals. At the same time, it's not guaranteed to make you happy, or even happier.

So if your personal goal is to be happy, pursuing "fun" is as good a way as any, and better than most. But if your desire is to feel the satsfaction of achieving difficult goals, "fun" isn't the most informative metric and pursuing fun isn't the most effective way.