I don't think anything in distutils can solve whatever the problem is that people perceive.
All I can say about the patch is that it apparently doesn't do any harm. I expect that, if it is accepted, people continue complain that "it doesn't work". Unfortunately, Michal Čihař never indicated what *specific* problem this patch is supposed to solve, so it is difficult to tell whether it actually achieves that objective (the literal description "64-bit things should go to /lib64" is not achieved by the patch - it never mentions "lib64".