Yeah and it was a collaboration between Microsoft and the PSF. A lot of tutorials written for macOS and Linux literally do start with "type in python and see what happens next" and both Microsoft and the PSF were seeing complaints that on Windows nothing happened but an error message. Microsoft didn't want the maintenance burden (that macOS and Linux has) of supporting and shipping an officially bundled version (and accidentally stuck on older releases as things start to depend on it or what have you), and meanwhile the PSF realized they were excited to get Python officially into the Store (and take on the maintenance of that) as possibly the easiest way to bring in new users on Windows. (As someone who has used Python on Windows for a very long time, I welcome the Store version as really the easiest install path to date.)

(ETA: The other reason Microsoft is less than willing to include scripting languages out of the box is past bad experiences with WScript. Doing it a shortcut to the Store install actually is a decent compromise from the malware we'd possibly see if Python scripts worked out of the box in fresh Windows installs.)