I think the implication is that MS went out of its way to make windows not compatible with others (or just appear to be by throwing bogus messages from xor encrypted obfuscated code).

E.g., MS windows 3.1 running in a window under Desqview ran faster than Windows 3.1 running natively. This was presumably embarrassing for Microsoft. Microsoft removed the operating mode that windows ran in that was supported by Desqview in Windows 3.11. Perhaps there were legitimate reasons for this feature removal, but breaking compatibility with a competitor's product would only be seen as a benefit by MS management, and is plausibly the exclusive reason for removing the feature.