I disagree. While I agree that web UI programming can undeniably be described as complex: a) JS, HTML and CSS have been designed to build more than "documents"

I disagree. While I agree that web UI programming can undeniably be described as complex: a) JS, HTML and CSS have been designed to build more than "documents" for over 10 years. b) Contrary to the idea that these technologies lead to bad API, I see many high impact graphics toolkits moving to a CSS / HTML driven model even when the teams working on these toolkits are not majority web developers. Quick examples: GTK3 and Source 2. c) There are many Javascript frameworks that do not require deep knowledge of all three of these technologies to produce something. The vast majority of Javascript UI toolkits, for example jQuery UI aim to remove the need for in-depth knowledge of HTML and CSS to produce user interfaces. d) While I agree with you that there is no one true way to tie together these technologies, I think there are solid abstractions that tie HTML, Javascript and CSS together. I've been very excited about how terse and powerful d3 is for composing any kind of HTML/JS/CSS model.