Unfortunately, you are at least partially right. HTML5+JS might be an acceptable solution to lots of problems, but I don't see web game development moving away

Unfortunately, you are at least partially right. HTML5+JS might be an acceptable solution to lots of problems, but I don't see web game development moving away from stuff like Flash and Unity to a W3C standard. It probably has a lot to do with having to wait forever while the W3C labors to push any damn thing out.