It’s really amazing docker isn’t more valuable, it has completely revolutionized software development. They just failed to pull in the enterprise cash in a meaningful way.
I think it's an issue of monetization. The things that underpin Docker are all open source kernel features of Linux that were being worked on separately anyways. Docker's value here is in wrapping that up into a nice useable package and offering a centralized repository. How much value does that actually add and more importantly, how do they monetize that? A lot of this kind of tech work winds up this way.
In my opinion a hell of a lot.
I was using LXCs before Docker and the experience wasn't too bad as long as you were running native Linux. That's not going to be possible for a lot of folks which means it's back to rolling your own manual VM, then figuring out how to do remote code editing not just to a VM but an LXC within a VM and then figuring out distribution of that along with a lot of other problems that Docker solves.
With Docker, it really is just install it and run 1-2 commands and a lot of major code editors know how to work with it too.