I agree with you esp. when it comes to GWT - going from Java to JavaScript is going from a terrible language to an ok one. There are two reasons why it has become popular:
Java programmers don't want to learn JavaScript
It comes with good UI building tools
If GWT didn't have good UI building tools, Java programmers wouldn't have any excuse not to learn JS and program normal web applications. But here's a tool that lets them use their existing Java knowledge to build halfway decent web GUIs.
This is just another example of how technologies are chosen by considerations other than objective technical merits.
This is just another example of how technologies are chosen by considerations other than objective technical merits.