There is of course.. a different argument to be made.
"The argument that Microsoft (and Apple to a lesser but significant degree, and likely a good number of other less prominent software companies) have held the computational technology sector back to be about 10-15 years behind where it would it could be today."
Let me try a different argument: the fact that Microsoft managed to unify the market for both hardware and software and impose a common standard was the single most important factor of the rise of computer technology, and has been of immense value to the world.
01) By creating a standard platform, "Wintel", a huge market was created for a specific kind of hardware.
Microsoft, by forcing the *concentration of resources* on a single platform (Wintel), is the single biggest reason and pretty much the only reason why there are many hundreds of millions of computer users today: the dominance of the Wintel platform lead to constantly expanding markets which enabled a technological and economic bootstrapping process in which each technological innovation could generate enough income to generate a succeeding technological innovation along with the economies of scale needed to make that innovation affordable - which further expanded the market. (I.e. we buy progressively more capability for progressively less money, in a continuing process).
Beyond the amortization of physical capital, economies of scale also include the intellectual efforts invested on a single platform, as opposed to being scattered over a variety of platforms. It should be clear to anyone that if the engineering talent invested in x86 were scattered over a large variety of incompatible cpus, then that talent would have been less effective and would have accomplished far less, expressing itself in a large number of more primitive but higher-priced processors. Computers would be far less capable, and far more expensive, than they are today.
(This process eventually effected all computer components and lead to the creation of new components; as the size of the existing market increased, investment become more economically sound, and invention and innovation increased as the probability of returns on the effort invested in invention and innovation increased.)
Bear in mind that the process and fabrication technology needed to actually manufacture the cpu also benefited from the increased market for computers, another extremely important factor in the commoditization of personal computing. When you buy, let's say, a new graphics card, you don't buy "photolithography" but it still needed to invented and sold at an affordable price, or that graphics card could not be fabricated in the first place.
Or, to put it another way, you wouldn't be able to run any FOSS on modern hardware if Wintel hadn't created the economic incentives that enabled modern hardware to exist in the first place.
02) Wintel's dominance enabled economies of scale in programming too! In much the same was as with hardware, it did so by concentrating immense intellectual investment on a specific platform, thereby making for more rapid progress than would have been the case with only a small number of people investing their effort. Had this same quantity of intellectual investment been scattered of many platforms, none of them would have progressed as far as they have.
All of this should be familiar to anyone with a moderate degree of economic literacy, or who is familiar with the career of Cornelius Vanderbilt (a group of people probably to a large degree co-extensive with the first, now that I think about it.)
03) The fact that computers were so affordable created a mass market for them, which encouraged the adaption of the technology to a mass market - what I have in mind here are GUI's, without which we would still be using the command line. The development of GUI's made computing far more accessible to a mass market .
04) The ubiquity of Windows enables computer skills learned at one enterprise to be transferred easily to another enterprise, if they both run Windows. (And most do.) This creates a more capable workforce, allowing for increased productivity. It also allows for greater employee mobility, from enterprise to enterprise, although such mobility is greatly effected by other factors too, of course.
(Of course, if you think that all of the foregoing is "evil", no one will stop you. But please pay careful attention to the following statement:)
What anyone thinks of Microsoft's business ethics is irrelevant. It is easy to moralistically examine anyone's behaviour in the real world and find it unacceptable. The actual outcome of Microsoft's behaviour has been immensely beneficial to the progress of personal computing, IT, and everything based on it, including all forms of consumer electronics such as smart phones, dvd players, mp3 players, digital cameras and so.