Relative to the .NET stack, Python's toolchain has always been no-cost for anyone to use, and the language is so fun that there are many people who enjoy just coding in it for free.

I can almost see these guys' angle, of why they might see this as a possible threat that could undermine their career. .NET coding pays well, and is usually semi-exclusive to those who previously had an employer pay for them to use the tools, even though that's not theoretically necessary.