Making highly interactive web apps in 2013 was painful and it is revisionist history to claim otherwise. Keyword being “highly interactive”. If you’ve been mostly building traditional sites then it’s a different situation.
The author says he likes Knockout… well, I respect Knockout too, but having spent many years maintaining a decade-old enterprise Knockout app, it is painfully clear that React was actually real progress.
These frameworks - warts and all - do solve real problems. Just as you shouldn’t trust someone who tells you they’re perfect, nor should you trust someone who dismisses them as a con.