This is totally true. We are trying to maintain a codebase that is hundreds of thousands of lines of code, based on Drupal 5. It's a fucking nightmare.
I have worked on my fair share of Python monstrosities. To be fair I think I have seen worse in PHP, but I don't think the language itself is going to save you from shit architecture.
I used to use drupal and it was a nightmare. I switched to Django just because of python and it was the best decision I’ve ever made in regards to web development.