I have a bigger rant about web components, and polymer and interesting enough, I believe - none except one - of the article owner's comments matter much.
Here's another rant and what currently sucks at web components (for us)
1. Still no adequate browser support coverage (OP's point) - Google polymer team keeps the mood up, is excited and does great things but we're still waiting
-- for Firefox to support it, (which declined to implement html imports). I kind of think Mozilla is sabotaging the efforts for some political reason after reading their comments.
-- for Safari 10.2 to support it natively
-- for Edge to care.
Unless all the browsers support the v1 spec, we end up being just another JS framework and the Polyfill webcomponent-lite.js itself becomes a framework in competition with vue, react, riot, and others.
2. Web components (especially) polymer ones are not a good citizen inside an HTML page next to others.
-- Due to component scoping (which is ok), style scoping in the main document css (custom style) (which is weird) and DOM and shadow dom, you end up feeling hopeless at some point.
-- I just want to use the paper-toggle and I end up downloading 100s of files.
3. The opposite of "it just works" ( as someone wrote somewhere, kind of, like you invented the opposite of it just works.)
- Polymer, and the paper, iron and other libraries are cool, but they somehow fail silently and often. It's hard to figure out what went wrong.
4. Polymer team is trying to replicate the cool other JS tech and tools, and it just lags behind. (ES6 in polymer 2.0, the still beta app router, bower, gulp and OMG.js ....)
5. The iron, and then paper, and other elements are too heavily interdependent and no other leaner library or collection appears in sight.
- A lot of nested imports
- and the hopeless the wait for HTTP/2 and the future web of 2020s.
I will write later what can be done.