Why did Internet Explorer ceased evolving

This is an excerpt from How Microsoft lost the API War that give a really good explanation to the lack of any improvement to Internet Explorer in the last years:

Which means, suddenly, Microsoft’s API doesn’t matter so much. Web applications don’t require Windows.

It’s not that Microsoft didn’t notice this was happening. Of course they did, and when the implications became clear, they slammed on the brakes. Promising new technologies like HTAs and DHTML were stopped in their tracks. The Internet Explorer team seems to have disappeared; they have been completely missing in action for several years. There’s no way Microsoft is going to allow DHTML to get any better than it already is: it’s just too dangerous to their core business, the rich client.

[“Rich client” here means a Windows application]

So Microsoft see in Internet Explorer a threat to it’s own interests and the project is put to rest. My opinion is that this is not sustainable for long term because the competition will eventually evolve beyond IE. Soon or later, a “killer app” will appear needing a better browser and then people won’t hesitate much to switch platform so that they can use it — the platform here is the browser. This is what always happens with gaming consoles. It’s not like if it was complicated, or costly, to switch browser today.