Microsoft doesn't have a monopoly over operating systems in general, and google doesn't have a monopoly over search. But I think microsoft does have a monopoly when it comes to running most of the programs that a business already has. You can more or less replace unix with unix but you can't replace microsoft with anything and expect existing systems to still work. Hopefully reactos will reach this point but it's not there yet.
>>you can't replace microsoft with anything and expect existing systems to still work. Hopefully reactos will reach this point but it's not there yet.
That will be impossible in practice.
It is in a monopoly's interest to not be compatible, so they will make complex systems that will be expensive and take a long time to be bug-compatible with. And when the APIs are cloned, they will have gone to something else. All this will also be well locked down with patents.
The worst part (well, worst for me) is that the resulting systems will be unnecessarily complex and hence unpleasant to use for developers. That is, it lowers my life quality if I work with their systems.