Even with correct PATH management, Windows still hijacks the command when python is not installed; that it the mechanism it uses to advise you to install it. Linux distributions use a different mechanism that maintain the expected behaviour of there not being any program/comnand called "python" when python is not installed.

Windows solution in this case is a lazy hack that makes the system more brittle.

As an aside, Linux distributions tend not to have this sort of PATH management issue because (for better or worse) they tend not to modify PATH when installing software.