[pcwalton]

The choice isn't between "support HTML/CSS/JS" and "don't support HTML/CSS/JS". No Web browser can drop backwards compatibility. We haven't even been able to get rid of backwards compatibility for much worse things than CSS, such as <center>, because sites you need to use (such as Hacker News) won't update their markup to use CSS for layout.

asm.js is attractive because it is a small extension to the Web platform, so the overall additional complexity of an HTML/CSS/JS engine (which we are likely never going to be able to drop) doesn't go up much by implementing asm.js optimizations.

[teacup50]

Meanwhile, platforms that don't even try to wedge their technology into the HTML/CSS/JS universe have better applications.

[pcwalton]

We're talking about Web browsers. Technologies that try to integrate into Web browsers specifically but don't have a good compatibility story with the platform haven't had a lot of success.

[mambodog]

Some examples of non-standard extensions which have fallen by the wayside (or failed outright):

    ActiveX
    Java Applets
    Flash
    Silverlight
    VBScript (and other non-JS scripting langs)
    NaCL
    Dart (via a native VM)

[azakai]

In some ways they do, but they are also nonstandard, with the downsides that that brings. Neither overall approach is perfect, it's good that we have a combination of both in our field.

[WorldWideWayne]

Why get hung up on the fact that something is non-standard? Things don't just pop into existence as a standard way of doing things. Some core group of people has to agree on them and then away we go - we have a standard!

That's why everybody should actively use non-standard things that they want to become standards.