> plenty of great server-side languages and environments

Depending on the type of project, I would choose PHP over at least some of the languages you mentioned; I guess "great" is not a significant quality when making architectural choices.

Just to be clear: I was thinking about factors like performance, choice of servers, how easy it is to hire good developers, library ecosystem etc.

EDIT: obviously the "awesome aspects" mentioned by GP are a similarly unsubstantiated claim ;-)