You're correct about it being a tough market, but you (and your commenters) wrong about nearly everything else. It's tough because industrial giants are slow moving, and very particular about certain hard things (reliability and being real, mostly) that are actually hard. To contrast, media companies are fast moving and very particular about
expensive things (art and design), but are bloody cheap and don't mind smoke-and-mirrors. This is why consumer AR is hard, but industrial AR is "easier".
Source: Early Daqri employee (when marketing apps were the thing), and industrial solutions architect at the same while they had any. (No longer work there)
There is a bejeebus amount of money in the industrial sector for these kinds of solutions, although at first glance it might not be clearly "AR", although you would use pretty much exactly the same technology.
First up - although there's not a lot of information, the information that IS present is staggeringly decisive:
https://www.youtube.com/watch?v=P-qJ6U-ixX0&feature=youtu.be...
http://www.recode.net/2015/6/8/11563374/boeing-says-augmente...
TL;DR - ~70% time spend with <10% errors made on a first-time assembly task, when using AR instructions vs classic instructions. Gains are (mostly) kept even if you stop using AR on subsequent assemblies.
Second up -
My favorite anecdote from a boss, about building satellites: Once, while building this $100m+ object, they got to the end and found a left over bolt. They then had to spend a giant chunk of money taking the thing back apart, first to find where that bolt was supposed to go (and put it there), and then to prove that nothing else was missing.
If you're doing AR-instructions, not only are you (probably) not going to make that mistake in the first place (>90% error reduction), but you're going to have video records (ideally already in a reality-capture format, rather than just raw feeds) to review instead of an expensive disassembly, to prove nothing else is wrong.
This mistake was worth tens of millions, and mistakes of this cost-magnitude are so common they're part of the costing structure. You expect them.
As a counter examples to my points, we once looked at document pick-and-place for a document storage company. The value they'd get from the AR, after development and equipment costs were factored in, just didn't make sense. Another company wanted to use AR tech as a replacement for existing industrial quality checks (parts fly by on a conveyer, how do you know if they'd been made correctly?). AFAIK, what they wanted to do is still basically impossible. Finally, there was an ongoing debate as to whether it'd make sense for people building buildings to use industrial AR (everyone? only managers / shift leads / etc?). AFAIK, there are still issues with making that happen, although people are making solid progress.
Finally, you're forgetting about the value of a hands-free display; which is an AR headset minus the computer vision; if you've ever spent time in a facility (which is so totally awesome and I miss those trips) it's pretty clear why that's valuable.
So you're right about a couple of things - it's still hard, and you still have to run the numbers to see if makes sense for your situation (or which people in your situation) - but you're essentially wrong about the application opportunities, and the numbers usually work out amazingly well.
Any questions? Happy to answer what I think I'm allowed to.