There is much truth in this post.
Perhaps controversially, I think Microsoft's real "B2B" success comes from treating end users like crap. Arguably their only successful "end user" product line is Gaming, and that (on Windows) has grown with comparatively modest investment on Microsoft's part or with phenomenal (bought, third-party IP-based) software and a bucketload of cash (Xbox division).
Microsoft's true success in the business world comes from ultimately targeting managers – be they in an IT department or otherwise. They are afforded real power over users. GPC can deny a user the ability to do something with their computer that other users can do. Permissions can be very finely grained. Office has, for many years, come with some form of document-based DRM. Microsoft as a company seems to love DRM; they invented activation, for god's sake. The net result of this is that they know what managers like, which is, in fact, to manage. They centralise. They absorb. They have created a huge, confusing, proprietary computer-verse completely orthogonal to the rest of the world (except inasmuch as the rest of the world needs to interact with it).
A lot of their product line boils down to implementing MBA newspeek in disguise: clearly; writing good web software is difficult and a good business-orientated app features database, GUI and user-interaction parts – thus Dynamics CRM is born. It's not the business's "core competence" to redevelop those skills -- they're hard. Tie it in with their other B2B offerings and you have central control over both employees' performance, and customer's offerings, in a very tailored, swish way. Sure, other companies can do this (looking at you, Salesforce) but this is just one example. Salesforce can't also do, say, long-term archival storage on Azure for less than a cent per GB, and won't provide you with a calendar-and-meeting-filled video-chat app that is "free" with your existing subscriptions.
All of these things tick boxes. They provide "return" on the "investment" of paying the microsoft tax. The broader their product offering, no matter how shit it is to the poor saps that have to use it, the cheaper it effectively becomes. That's the true success of microsoft: they've always been big enough to do things well enough, conglomorate enough stuff, and amortise its effective cost over lots of different offerings. The net result looks good on an Excel spreadsheet, features that managers care about are there - and they keep getting business. (And end-users be damned!)