This is not 100% accurate. The "standard" install will place the installation directory higher in the PATH priority. The store version doesn't modify the path.

This is not 100% accurate. The "standard" install will place the installation directory higher in the PATH priority. The store version doesn't modify the path. Instead it creates app execution aliases for the executables it installs. As of version 3.8.2 it creates the following app execution aliases: idle.exe, idle3.8.exe, idle3.exe, pip.exe, pip3.8.exe, pip.exe, python.exe, python3.8.exe, python3.exe, pythonw.exe, pythonw3.8.exe, and pythonw3.exe. These can be found in the %LOCALAPPDATA%\Microsoft\WindowsApps directory. Prior to installation the python.exe and python3.exe app execution aliases in this directory will launch the Microsoft Store. After installation of the "store" python they will actually launch python.