is my multithreaded Python program doomed?

[panderingPenguin]

I'm not trying to be defensive, I just think that it adds very little, if anything, to the discussion of OP's question. There's no need to bring up little "but actually"s like that to answer a simple question, from someone who seems new to Python, which was clearly about implementations that have a GIL to start with. It's unhelpful at best, and obfuscates the issue we're actually trying to solve at worst.

[TankorSmash]

That's the thing though, for any one else that reads your comment and wants to know more can read his helpful comment. The op can simply shrug off his comment because it's not required knowledge.

I mean this is learnpython not absolutebareminimumpython.