The key is living below your means by ~30%. You make 150k? Live like you make 100k. Every time you get a raise, 30% goes towards investing. For most engineers this is achievable.

Everyone getting income passively is not going to work for society in general. Work still needs to happen. Until we live in a post-scarsity society, if nobody works then everything collapses.

That's not to say that passive income is impossible, its just not going to work if large swaths of the population are doing it.