"(for example, Dell sells Linux PCs at higher prices than Windows ones even though Linux is free)."
This is due to the fact that the Windows install gets bundled with all the 3rd party crapware which companies pay to have installed on Dell machine. Once companies start paying to have their crapware bundled with Linux, then the prices will come down.
"The result is that Microsoft gets guaranteed revenue from a product few would freely choose if software and hardware was compatible with all OSs and these OSs were choices given to the market."
Average Joe doesn't care about the OS, he just wants a computer that does what he wants. The 2nd half of your sentence wouldn't even be true if Windows didn't exist anyway. There are plenty of non-Windows specific applications and hardware which don't work on both Linux and OSX (and all the other minor OSes out there).
"Microsoft also uses effectively government bribes in developing countries to get their software installed"
Doing business in most devloping countries requires this because their governments are corrupt. This isn't unique to Mircosoft by a long shot.
"The Xbox 360 represents the end result of this: you can dominate a market with cash alone."
360 represents capitalism.
"The studios, by the way, were bought with the aim of damaging competitors"
There is currently an article on /. that suggest that Sony paid Warner $400 million to go Blu-ray exclusive. Are you boycotting Sony too? What about numerous other companies? This is just another part of big business.
"Mac gaming would have been common"
Halo was to be a simultaneous release on both Mac and Windows. No other dual releases have dramatically changed the Mac gaming landscape, so why would Halo? Even assuming Halo was to be Mac only, look back to Marthon. It was groundbreaking on Mac yet gamers didn't jump over in droves, why would another Bungie game have done this?
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I'm not saying that MS doesn't have blood on their hands, they do, but so do many other companies. Your perfectly welcome to not purchase their products as well, but you single MS out for reasons which numerous companies have also done. If you want to take a moral high ground then why not refuse to purchase products made in China as well? They have a horrendous human rights record and I'd consider this far worse than an absusive monopoly.
