[kapowaz]

This is true, but because of completely different toolchains it's very rarely the case that this happens. Flash, at its height, was being used with tools like Flex to build full applications. Adobe provided interface libraries for you to substitute native controls for its own (inferior) versions. Nothing like this exists yet for the tools you mention, and hopefully never will..

[roarroar]

And you think asm.js/WebGL will be any different? The more powerful the browser gets the more open to this kind of abuse it will be. Live with it.

[kapowaz]

Being open to abuse and being something that is commercially viable and desirable are totally different things. Yes, you can do all manner of nefarious things with native web technologies — as I understand it, this was one of the reasons it took so long for a native JS fullscreen API to be implemented, as it would open the door to spoofing the operating system's interface chrome.

But where these technologies differ is that Flash was marketed as a one-size-fits-all solution, that allowed designers and developers to work inside of a single framework. The barrier to entry is also very low: you can achieve a lot (relatively speaking) without much technical expertise — certainly when compared to how much effort it might be to do things the right way with native tech.

I don't ever see this happening with the likes of asm.js or WebGL because they're much more narrow in focus, plus they require very different (and non-trivial) skillsets to those of designers. As soon as an endeavour like this requires multiple developers and designers, it no longer appeals to your common or garden ‘chuck it over the wall’ marketing agency; the only ones that can afford to invest in this are the ones using the tools appropriately (or at least, most of them will be).