I agree with everything you said, but (in Microsoft's eyes) this is a feature - not a bug.

Without this cloud component, how could:

• Microsoft make sure that the accounting team does not introduce a malicious/old Python library into the Excel file?
• Microsoft protect its users from writing/running inefficient, buggy, or malicious Python code?
• Microsoft provide a Python runtime to users who do not know how to install Python?
• Microsoft charge to run code that you wrote in a free, open source software programming language on a device that you own?