Way back in the day I used to be a Microsoft developer. I got tired of them changing the database API every other year. All the open sources platforms are much more stable. Knowledge in these other platforms doesn't decay as quickly or is at least somewhat useful even after 10 years.
In contrast, Microsoft will just go and kill whole platforms from time to time (e.g Visual Basic) rendering useless years of experience building deep understanding of a platform.
A far worse language with enormous hordes of programmers who had bet their careers on it.
"Classic" VB was the PHP of the client/server era: ugly, reasonably capable, and everywhere.
Imagine the screams you would be hearing across the Internet if the PHP core devs all decided en masse to go work on something else, and PHP was under a closed, proprietary license so nobody could fork it, and you get a sense for what it was like when Microsoft killed VB.
ODBC, which, along with every other database API released by Microsoft in the past decade, is not supported in Metro. Astonishingly, it currently appears to be easier to query a Microsoft SQL Server from an iOS app than from a Metro-style app. Presumably someone could port ODBC and a driver like FreeTDS to Metro, but it'd be made more difficult by the radically different networking APIs, and would still suffer from annoying limitations like the inability to connect to local database server instances (per Windows Store policy).
I think Microsoft is worse about it that other commercial vendors. Perhaps due to a perception (not necessarily incorrect) on their part that their customers are locked in.
If a vendor who only supplies a single product decides to torpedo the APIs that you rely on, they create an easy opportunity for you to switch to another vendor entirely. Whereas historically Microsoft could wreak havoc upon an entire development platform (Visual Basic) knowing that probably all you'll be able to do about it is huff and puff around a bit on the Internet. After all you couldn't jump ship on Windows development - all your customers were Windows users, or your entire IT department was built around Windows, or your corporate intranet is all dependent on IE6, or whatever.
Funny you say that, because Microsoft's software problems are often attributed to bending over backwards to be backward compatible while other vendors like Apple quickly kills compatibility with almost ever release, with even point releases.
Take this game bundled with Windows 95. ftp://ftp.microsoft.com/deskapps/games/public/AAS/Hover.exe
It runs even on Windows 8. Upgrading from Windows 1.0 to Windows 7.
As I said in another comment, I still see some ASP and Visual Basic usage even after all these years, those applications are still supported in Windows 8 and Windows Server 2012. Microsoft stopped making new versions because it wanted to move on to better technology. Want to take a poll on HN about what developers think of Visual Basic and Classic ASP? A case of damned if they do, damned if they don't.
Right, but this is largely orthogonal to the problems with Metro on the desktop. Sandboxed Mac App Store apps are limited, but need not be written against an entirely new set of APIs that is not only unsupported by previous versions of the OS, but unsupported by non-App Store apps running on the current OS version. Say what you will about the Mac App Store, it at least doesn't suffer from all the problems inherent in the iOS App Store model. Metro does.
I am sure there are a lot of people who rejoiced at Microsoft "killing" Visual Basic. And I say "killing" because I see a lot of it in use, they just stopped adding new features to it, the old applications written in the early 90s still work in Windows 8. Try that with other OSes or GUI toolkits.
In contrast, Microsoft will just go and kill whole platforms from time to time (e.g Visual Basic) rendering useless years of experience building deep understanding of a platform.