Just a note about company backed projects. I backed Google Web Toolkit a few years back. Big mistake.
The problem with GWT is that newer Google-associated projects are perceived by some people as better (and the comparison is not always apt): Web Components, Polymer, Dart, Angular, etc.
But that doesn't somehow make GWT any _worse_ than it was before, and it's still improving. The compiler is faster, they're adding Java 8 features like lambdas, the JS interop is better, they're tracking web APIs closer, and I think they have a even plan for web components integration.
I used to use GWT extensively, and I would be one of the ones to argue that it's approach was great at one time, and probably a bit outdated now, but it's not abandoned and it's evolving to fit better with today's modern browsers. I might not choose it today, but I wouldn't regret choosing it a few years back, or be in a huge rush to move off of it if I had a large codebase.
I still believe it's doomed though just because I don't believe they can match the pace of the JS world.
At the time I loved using it as it had many nice features. But sadly it's very hard to migrate from. Most importantly is the vendor lock-in with the 2 framework specific RPC mechanisms used to communicate to the server.
The main reason I'm glad not to use GWT is that I enjoy developing in Javascript a lot more than I do in GWT (Java). I have found that I can implement, modify, or troubleshoot a UI roughly an order of magnitude faster than I used to be able to do it with GWT. This is due to a combination of being able to reload by refreshing my browser (no slow re-compilation steps), as well as being able to inspect elements/styles directly in the Chrome dev tools.
There are about an order of magnitude (or more!) people who write about Javascript, or $FrameworkOfChoice (Angular, Backbone, etc) than there are that write about GWT. This includes both blogs and Stack Overflow, not to mention examples on JSFiddle or the like.
GWT doesn't easily let me integrate other Javascript libraries or components, so you have to implement your crappy version of Chosen (or similar) yourself. There's no JQuery or Underscore or similar, because it's all Java (basically).
The Chrome Dev Tools or Firebug are >>> the GWT debugger. The GWT Dev Mode plugins required for debugging, is also no longer supported in Chrome, and soon in Firefox. (I discovered this last week, the first time I've touched GWT in half a year. There's a newer Dev Tools alternative, but I've been unable to actually get it working.)
Javascript testing tools (Jasmine, phantomJS, etc) and build tools are now a MUCH more mature ecosystem than they were when GWT was first invented. We used to use a combo of JUnit + Watir/Selenium to test our UI, and now we can do similar with Javascript frameworks in a less fragile way.
In summary, GWT was awesome, but I see no reason to use it today. It helped me find my current job, so I'm grateful for that. However, if you were looking for a web framework, you would be much better served (IMO) if you chose React, Angular, or Ember rather than GWT.
All of your points are true and well written, but at the end of the day, I don't want to write and maintain large apps in JavaScript (or really in any dynamically typed language for that matter). GWT is still the best way to avoid that.