Can ArcPy be used without installing ArcGIS Pro?

Answer

It is possible to use ArcPy without having ArcGIS Pro installed on the machine. However, another application must be installed to be able to use ArcPy, such as ArcGIS Server. ArcPy is a site package that is part of the default Python distribution in the arcgispro-py3 Python environment with ArcGIS Pro and ArcGIS Server. If neither ArcGIS Pro nor ArcGIS Server is installed locally on the machine, ArcPy cannot locate its license.