Nobody is upset, really. Java web client lost a very long time ago to Flash.

But imagine, if 25 years ago you poured your heart and soul years ago into a project because it promised to be a particular kind of great (but later failed), it can sort of drive the knife deeper and throw extra salt in the wound when your project's ugly red-headed stepchild (i.e. JavaScript) grows up into something great and gives birth years later to a beautiful standard (asm.js, later WebAssembly) that becomes what your project thought it would be, and much more. Or something like that.

Java certainly has a well-established place in software, no doubt about that. But its original promises had it (combined with AWT/Swing, applets, and XML, ... umm yeah) becoming the ultimate "write once run everywhere" platform that could scale up to massive servers and down to tiny embedded chips, and every client platform in between. In retrospect, C# and .NET would have done well not to attempt to emulate Java's initial scope.