The concept of "passive income" is almost a scissor concept. Or maybe only if you couple it with the categorical imperitive. On the one hand, it's so obviously true that it would be great to have passive income. Draw the salary you're drawing now, with some growth, and not have to work. On the other hand, if everyone had access to this capability then society and civilization would grind to a halt. People make things…
(First, "passive income" means "almost hands off, but not entirely")
Progress in technology is making things - better quality, less effort. Amazon Warehouses for example. Just a few years ago they took at least a few dozen people in rotation, now takes a man and a dog - the man to feed the dog and the dog to bite the man if he falls asleep.
Since so much can be done with so little effort it seems natural that if wealth doesn't concentrate at the top then most people would have essentially passive income streams.