You say "correct" but you're directly contradicting the parent's point, since with your argument the easily and correctly parsed 'Linux Subsystem "for Windows"' would not run afoul of any trademarks.
Remember -- the name "Linux" is trademarked. Microsoft is free to call something Windows X since they own the Windows trademark, but they can't call something Linux X because they don't own the Linux trademark. But they can call something X for Linux the same way a third party can call something X for Windows. Hence, Windows Subsystem for Linux. It sounds dumb, but that's the legal rationale.
