I don't think we are talking about the same type of software? The type I was talking about will only ever run on Linux because it's a (HTTP-ish) server that wil

I don't think we are talking about the same type of software? The type I was talking about will only ever run on Linux because it's a (HTTP-ish) server that will only ever run on Linux. Probably a server that is only ever run by a single company on a single CPU type. That company will have complete control of the OS stack, so if it says no Windows, then no Windows has to be supported.