There is a discussion with some insight into the technical reasons why they don't support Windows 7: https://discuss.python.org/t/windows-7-support-for-python-3-... (summary: api-ms-win-core-path-l1-1-0.dll is not available on Windows 7, so they'd have to switch from static import to feature detection + dynamic import in several places; and the Python team don't have access to Windows 7 so they can't do testing).

An unofficial Python installer for Windows 7 exists: https://github.com/adang1345/PythonWin7 (it uses an unofficial implementation of api-ms-win-core-path-l1-1-0.dll).