People asked me if Delphi will still be around 15 years ago, I was a huge fan of Delphi using Delphi 7 at the time coming from a Pascal background and since then Delphi has almost vanished into obscurity after Borland dropped Delphi for C++ Builder and Java.
Strange things started happening to it, it started compiling to C# then C# got dropped, then another company (Embarco) took it over and it is still somehow maintained and used by die-hard fans, a lot of them still running on ancient versions of Windows.
What happened to GWT? Back in 2011 Google pulled out of GWT and started working on Dart. Vaadin took over GWT and since Google pulled most of their engineers out of the project, you can see how drastic their release schedule slowed down (a release almost every month VS 2015 only one beta release): gwtproject.org/release-notes.html
Just like with GWT, Jquery was developed to work around browser incompatibilities (especially IE), since browser incompatibilities are rapidly becoming less and less since MS started moving in a different direction, I believe there will be less and less arguments for using Jquery and it will go the same route as GWT or even Delphi, especially if their founders move on to greener pastures; another group / company will take it over and keep it breathing, even if only enough to keep it from going extinct, but it will be dead for all practical purposes.