> PHP has a massive upside over Python: You don't need to restart your application when you change the code.

I see this as a downside: hot-reloading is something that should be part of your developer toolbox, not a feature of the language runtime itself. Otherwise, deployments are harder because by the time you’ve completely uploaded all your updated PHP files, the server already started to execute the code in the ones uploaded so far. Also, I hope you have a caching mechanism otherwise this "read the code from disk every time you want to execute it" must be a performance nightmare.