Like every human exchange, you don't have to be an altruist for your deed to be good. It's alright to do "good" even if it derives some sort of benefit for yourself or your company.
But a lot of people are saying 1) this doesn't offer anything educationally that wasn't already available and 2) introduces users to restrictions that will ultimately be costs to their educational development.
There is 3) teachers will be familiar with Windows and thus more able to offer computer education with it. You can do real stuff on a Windows machine, but most of what I see on Windows machines in schools is "here kids, this is how you work Excel / Word Powerpoint". Frankly I worry that inner city schools will be blanketed with these things, with token "computer education" offered on them, and everyone congratulating themselves on addressing the technology gap while the kids learn some Office and not much more.
Doesn't that say that the tools / model being offered here is fundamentally broken? If you can't give it away without slowing down the progress you're trying to help, that's a problem.
there are plenty of "business-oriented decisions" that are bad for others; being pro-competition or anti-monopoly is not the same thing as being anti-business in general, as you seem to be implying here.
the poster was talking about Microsoft's use of network effects as an anti-competitive strategy, not about criticizing a company attempting to make money.
What is important is how it affects me and my interests.