It's only surprising if you don't understand that Mozilla's core mission now is to promote a permanent JavaScript monopoly. Mozilla has committed to blocking any technology which could ever offer equal support to any other languages. Now they cannot even allow plugins unless they are based on JavaScript. "The Web" used to mean web pages and HTTP, now "The Open Web" and "Web Technologies" mean we are forced to work with a growing mountain of ill-considered, weird and unsafe "bad parts" forever.
In a strikingly similar parallel dimension, vendors have applied pressure to ensure that networked PCs would only run COBOL, and other languages could only be supported by compiling to a subset of COBOL that inherited its semantics so that nothing would ever be faster than COBOL. In that parallel dimension, this restriction is known as "Open Web", although nobody knows what is open about it.
It's not about that. Even if I liked COBOL, I wouldn't want a world where only COBOL can be used. And it doesn't make sense that this world has to be artificially enforced when there is demand for variety.
Not sure what you mean by the "same basic semantics". I think the semantics of Go and Elm are quite far away from JavaScript. Dart less so, but it's enough to change the developer experience quite a bit.
I don't particularly like x86 instructions, but they also don't bother me that often.
Granted that JavaScript isn't sufficiently hidden yet, particularly in debuggers. That will take a few years. On the other hand, it's significantly more readable than assembly and getting better, so as a compiler target language, I think it will work out okay.
The forces here are no more artificial than the ones that made the industry standardize on x86 and (later) ARM. Popular, accepted standards become more popular when the barriers to alternatives are very high, as can be shown by the people who tried and failed with strong alternatives.
In a strikingly similar parallel dimension, vendors have applied pressure to ensure that networked PCs would only run COBOL, and other languages could only be supported by compiling to a subset of COBOL that inherited its semantics so that nothing would ever be faster than COBOL. In that parallel dimension, this restriction is known as "Open Web", although nobody knows what is open about it.