PHP has value types - the one "every data structure at once" type gets deep copied when you pass it to another function. That's enough to make it a good programming language, whereas Python is unnecessarily 90s class-based OOP with reference types.

I don't quite understand what you mean here. Do you have an example?

If you have a dictionary and pass it around to someone else's code and it gets changed, those changes affect your code too instead of copying it, which is annoying and less safe.