Many of the software that people install on Windows are quite expensive. So if any package manager were worth calling a "store", one for Windows definitely would be.

It doesn't make sense to have one package manager for paid software and another for free software, so both types of software would be available in the same "store", with the unfortunate consequence that you need to log in with a Microsoft account in order to get free software.

But if I only used free software, I wouldn't even be using Windows.

The non-developer / non-power-user is likely already using their Microsoft account to log into the OS.