1)
Python seems simple at first glance. There are a lot of points that
always need to keep in mind. Since 2003 I used Python because it was
simple. Since 2016 I use Emacs Lisp instead of Python for disposable
tasks, prototypes and text processing.
2) Backward incompatibility of language and libraries more than of Java, Delphi or Emacs.
3)
Dynamic typing per se. This is good for little project/team but, it is a
pain in another case. I wrote a library for type checking in a big
project.
4) Dynamic typing implementation
makes Python slow. Even slower than Emacs Lisp. Common Lisp
implementations prove that dynamically typed languages could be faster.