Who is this guy of seemingly infinite wisdom?
(https://goodreads.com/author/...)

I’m not sure. But

“Failing to plan is planning to fail”

Is an ancient quote. So maybe this guy is just quoting quotes rather than inventing them?

The first is an ancient proverb as well, recycled by a lot of rich / successful assholes today.

I have read lots of quotes from Confucius and Laozi. These were translated from Mandarin chinese to English. So there is a possibility that some meaning might have lost in translation, but all things aside, I see most of these quotes repeated by people, just rewording a bit.