If you're trying to install the MSIX build of Affinity on Windows and it's failing with the following reason:
Windows cannot install package ... because this package is not compatible with the device. The package requires OS version 10.0.19041.0 or higher on the Windows.Desktop device family. The device is currently running OS version 10.0.xxxxx.xxx. (0x80073cfd)
This indicates that your version of Windows is not supported. Our apps require Windows 11 or Windows 10 May 2020 Update (2004, 20H1, build 19041) or later to install.