To make sure I understand correctly:

On platform ABC the value 1 could mean SOCK_STREAM but on platform XYZ SOCK_STREAM is value 32?

Assuming the need to pickle socket types is not new, then people have been doing it, possibly with painful workarounds, on the integer values until now, and suddenly changing the pickle of a socket type from an integer into a string is going to break code.

Or am I missing something?