different purposes -> different languages. I don't go for those religious things.... but PHP != Java != JS != Ruby != ....
write a desktop app in PHP ;D .... sure you can do it .... but probably you should switch to another language for that.
And the most important thing .... every language you know helps you understand other concepts. So stop being religious learn the overcomplicated hyperabstraction of java and than kick it for <please insert language here> and learn the next one.
All languages are built on models -> All models are wrong -> but some of them are usefull..
understanding paradigms helps you improve your programming skill.