Both have advantages but i would not use python in performance hungry core components. Maybe if wrapper to C like Numpy lib and not too many function calls. I tend to add parameters that can increase test periods exponentially. Atm its normal for test to take a week Waiting times with python would be too long (probably like week C++ vs month+ Python) And idk what to improve next if modifications are not tested. So in my case development speed and execution speed are both faster with C/C++. From: https://machinekoder.com/choosing-qt-for-python-or-qt-cpp/
A good developer is worth 200K annual. Will rather code in python and then buy 96 cores if performance is needed.
I don't think everything can benefit from parallel processing. Some things have to happen one after the other. Correct me if I'm wrong.
IMO its always better to work around a problem vs throw money at it. But yes developer time can cost more than hardware. In my country avg C++ dev salery was ~2k/month. At least 3-4 years ago when i checked statistics reported by devs. With experience and good problem solving skill 3-5k probably negotiable but rare. 16k/month in usa? after taxes?
In my case it could be parallelized even between server farm and each board could use 1tb+ ram to speed task up.