Once you experience the *nix was of doing things (after the initial learning curve), the Windows way is a huge pain in the ass.
On Windows, VS debugger beats everything else I've seen hands down.
It's not hard to support Windows if you're writing good cross-platform code; there are a lot of libraries (Qt, Boost, etc.) that make things much easier than they used to be.
Again, I see lack of Windows support mostly as programmers being lazy (and I've said the same thing about lack of 'nix support, so don't think I'm being biased).
If you don't write portable code you're doing it wrong.
Also, code portability for a project like this is important, but that's not universally true. Having a hard and fast requirement for code portability imposes a set of concerns, design and maintenance issues that complicates a project. It (almost) never comes for free, and is a legitimate concern for any project--even ones where a portability requirement is almost a given.
"Lazy" would imply that Windows support is somehow a requirement that's being shirked by developers, which frankly it isn't. Microsoft is not entitled to have developers support, expend effort on, or even give a moment's thought to their platforms.
And this attitude being displayed toward Microsoft is just lazy (and very likely the province of the young), because while they did give us a crappy browser and Webforms for way too long, and they are fun to poke fun at, they've done more than most companies to push both the computer revolution and the Internet as a whole forward to what it is today. So give them a little credit, pull your head outta the sand and actually take a look at what they do once in a while also. You might be surprised what you find.
As far as I'm concerned Microsoft has squandered any goodwill they may have been due, if they deserve any credit it is for driving me to open source.
As much as everyone bitches about them, the entire reason we even have affordable desktops and laptops enabling this magical open-source revolution is because of the work Microsoft did in the 80s and 90s.
That's like saying if Henry Ford had never mass produced cars, no one would have figured it out...
Yes MS created the PC ecosystem in the 90's, but if they hadn't, someone else would have (Apple? IBM? Maybe even Sun?). Market pressure would have eventually driven down prices, it always does...
Apple was busy shooting itself in the foot as a boutique brand. IBM was not interested in lowering prices. Sun (and SGI for that matter) were heavily wed to the workstation and high-end server market.
Microsoft (and Intel) by careful work made it possible for cheaper hardware to still run a product people wanted, and so create the market pressures you're referring to.
They were a pure software company, and used that to enable competition in the hardware market.
You need to narrow it down substantially for that claim to make any sense.
(as for their contributions, I'm not going to get started on what would just end in a flamewar - suffice to say we have very different views on what the computing world is likely to have looked like without MS)
Who uses Windows for native apps that are truly Windows exlusive? Even Microsoft Office is a web app now, it's on OSX and iOS, and can even be run on Linux if you're crafty enough. Windows-only games? Fewer and fewer.
I'd definitely argue that Windows is not a requirement, though going cross-platform is a bonus.
As far as giving MS credit, they have been open sourcing many of their projects, and playing a little nicer with the non-Windows ecosystem...
Please stop punishing users for your platform fanboyism. Really.
If it is useful at all on anything, for anything, then it is doing pretty well.
And, unless you are the sort of person for whom using another platform when necessary is no great stress, then perhaps you shouldn't even be looking at installing untested alpha-level software releases anyway.