I'd guess that Dropbox make most of their revenue from businesses that have large numbers of different computers. If you have a network of computers all running the same OS then sharing and sync'ing is relatively easy; Dropbox solves the pain where you don't have that. Any service that's Apple-only, or Windows-only, or even just perceived to be limited to a particular OS, isn't going to have much of an impact on Dropbox's bottom line.
> But aren't there whole government departments and other very big customers that are pretty much single-platform, usually Windows?
Would be interesting to know how much that class of customer uses services like this. I would assume primarily as part of a bigger package (e.g. if it comes with Office365 or Google Suite (or whatever that is called right now))?
