Python is FIOC, java uses too much memory, C is too inconvenient without a lot of up-front work, Arc seriously tries to use continuations between pageviews
Perl is a hassle to set up with nginx or fastcgi in general and mod_perl is a shit
Ruby is slower than generating your web page outputs via a vbscript to a microsoft word ActiveX component
PHP just werks most of the time, it's a curly-brace language with three-clause for loops, first-class strings and hashmaps and a pretty standard class inheritance structure if you want it. The worst problem it has (and the cause for some inconsistency) is it's absymally weak typing system (almost as bad as tcl).
The only alternative is probably something like C++