Clients never were reasonnable in their demands, nor did most of the site owner have good and simple tastes and care about efficiency, nor did half of the internet care about user experience first above everything else.
Saying that the use of js has because heavy handed is cool and fun, but for any serious discussion there should be more acknowledgment of why we are in this situation in the first place. I'm not sure it's so much worse than 5 years before, at least we can read most things on mobile devices.
As a side point, I've done project on ultra weak platforms were every js had to be hand written to gain speed and memory space. I wouldn't try to do the same on some cookie cutter corporate site with a 600k slideshow loading on the front page, where having easily replacable components and tried and true pieces to test on the 20 combinations of browsers is far more critical that cutting 20k of compressed script.