Many users copy&pastes their code into the answer editor, which sets the tab size to something like four spaces treated as single character. This screws the indentation up, the code often needs to be scrolled right and back to read. Since the tab can be inserted only by pasting anyway, wouldn't it be practical to replace it by two or four hard spaces?
Bad formatting is going to happen no matter how many automatic corrections are done.
A Python problem that can't be reproduced because of automatic changes to the indentation would be a Bad Thing(tm).
If someone wants excellent, free help, the burden's on them to format things in a legible way.