I disagree that the AMP cache is the main benefit of AMP. There are plenty of CDNs that give performance similar to, or better than the AMP cache.
The only benefit of AMP is that the pages are promoted higher in results.
Back to the main topic of the article, the same could be said for the desktop and the mobile phone. Developers and framework builders are constantly adding bloat as cpu/memory increase. Since most people aren't writing their own frameworks and many are importing large parts of their apps from npm/gems/etc, everyone gets hit with the bloat. It's a vicious cycle for sure.
It's a shame that so many open source authors add bloat into their packages in exchange for popularity. They want all the users so you get tons of code that's never used in 90% of projects.
The big example of the above is express. It's a terrible cycle as the vast majority of people learning JavaScript have hopped on the express bandwagon and are now creating APIs with mediocre performance by importing a massive webserver they often do not need.
Overall though, it seems to show that most people prefer convenience over accuracy and performance (passive aggressive stab at mongo?)