Closer to the truth is that Enterprise's stick with whatever it was that their developers were using when they developed the tool. That just happened to be Netscape/Mozilla browsers when some of these tools were written where I work.
Corporations fear things breaking. Retraining is rarely an issue for a browser upgrade. However, if someone pushes out a crap Chrome update like this and an LOB application goes pop then heads roll. Chrome is entirely out of band from their normal operations and skill sets so it just doesn't even get considered. It also has dubious unpredictable support lifecycles and a rate of change which would scare anyone. To use a car analogy: they want a 3 year old Volvo, not a 6 month old Tesla.
What's bad is when you have to cater to old, broken IE behavior because you have to support that part of the market. We're seeing much less of that and more just "IE doesn't support new feature X". That does hold back some of the newest stuff, but not having typed arrays is not at all comparable to having to support IE6, for instance.
Personally, I would be ecstatic if we can maintain for as long as possible this nearly even split of marketshare over three (desktop) browsers.
I've been working with some large enterprises in the past (50k+ employees), all of them only use IE and all of them are full with some crappy ActiveX software, some by HP, some homegrown, it's really full of that crap. :( Even software that would support multi-platform is crippled in a way that only Windows+IE works, because in the projects noone cares if some other browser or (god forbid) another OS is supported.
I just ran CLOC. We have 6.2 million lines of code in 14 different languages!
And yes, things break all the time, often for unknown or unexpected reasons, and it's sometimes close to impossible to figure out why and fix the bug.
The enterprise software world is scary.
Oh, and the entire site didn't work in IE6, it was developed / tested entirely targeting Firefox, despite the IE6 requirement being in the spec (and it ONLY needing to work with IE6).
the Outlook web interface was miles ahead of anything in the consumer space for years.