Your experience isn't in healthcare, finance, military, manufacturing or oil and gas (to pop a few verticals off the top of my stack), it would seem. Literally 80% of my (adult, American-enterprise-employed) students in 2015-2016 so far have IE9 as their desktop standard, and have to beg for a special exemption to be allowed to install Chrome or Firefox.
Seconded. I am working on a project at UCD Med Center for California Dept of Public Health, which includes a pilot tie-in with Epic (even if it's just Epic shaking hands with our system and putting a short task's page in a frame).
We started out in late spring / early summer back in 2015 saying we needed to support IE9, but that has since changed to 11. The notice from MS that nothing before 11 would be supported after January of this year (2016) forced the issue, I think.
Back when I worked at a financial company two years ago we sure had mandatory crusty old versions of IE, though. Except for the groups that got special permission to use a browser that actually worked for things they had to have.
Besides military (haven't done that in 10+ years), I'm in all those other verticals and more. All desktops now have IE11 (because MSFT pretty much says "you must") and Chrome.
I wasn't speaking figuratively when I said literally, you know. :)
It's a breath of fresh air when an enterprise student has a modern environment. But it's enough of an outlier (in my experience teaching all these different places) to still surprise me to hear when it's true.
I literally deal with students in every class, a not-small percentage of students, that are disallowed by domain policy from installing another browser.
Give it a year. Without MS support, they will be forced to give up these older versions. Of course by then, IE 11 will seem quite "vintage", but that's life.