It's always hard to talk about these differences because 90% of the time we're actually just chest beating and comparing the length of our respective community's e-penises.

When people complain about PHP they often mean that in an aesthetic, and in an academic sense, the designers of PHP have, arguably, made a lot of poor choices.

What they usually mean is, due to the low barrier of entry coupled with poor aesthetic design choices the PHP community at large seems to have poor engineering standards.

These all being Turing machines though don't prevent it from having quality engineering being applied to it, as is the case of Facebook.

So, the corollary to "only a poor craftsman blames his tools" is "when you only have a hammer everything starts looking like a nail".

I wonder how many people are paid to directly hack on a Ruby implementation vs Python (yay Google) or PHP (yay Facebook).