Yup, a lot of web apps are using ancient versions of JS libraries, aren't compatible cross browser, and updates are few and far between. The issue is with enterprise apps, you really need to have a solid release schedule/plan. If you update an app and say "You are now forced to use a new browser to get the functionality of this." you will piss off a lot of people.
It's much easier for the app developer to create poorly written hacks for the older js libraries, because they are less likely to force a browser requirement change.
For enterprise apps, 1.9 is going to be around for an extremely long time.
Then they will be left in the past. It's unreasonable to expect me to hold my own product back because of lazy corp IT depts.
Unless they are contributing more revenue than it takes to support them, screw them. For me at least, this is not remotely the case and I'm happy to leave them in the dust.
Internal IT departments have no, no, no incentive to upgrade browsers. "Surfing the internet" is not a reason for IT departments to upgrade.