It has been years since I read it, but iirc the main point was to build businesses that once they are up and running don't require much much work to keep bringing in money.

I suspect achieving what he was aiming for is much harder now than it was when he wrote the book, as the barrier to entry to starting businesses goes down and the competition continues to rise.

But I think there is still something to be said for the goal of building a "lifestyle" business rather than trying to build a hyper-growth startup. If you are strategizing through the lens of "How can I make enough money to survive and thrive with the minimal amount of time spent?" vs "How can I grow my business to $100m" you'll come up with very different plans.