Asking as someone who's mostly only written PHP (and some javascript, more recently): can you expand on this? What kind of "hope of a free lunch" is there with other languages?
The first is the promise of DSLs and meta programming, where you can tune the syntax of the language to more naturally express your problem domain. When this works it's beautiful, but sometimes it is a distraction and makes the code difficult to debug.
The second, which is conceptually very different but I find it can play out similarly, are rich type systems where you can hopefully build up your application as a series of well defined type relations and transformations. Again, when this works you get really robust, reliable, and easy to modify software but there are often cross cutting concerns or business practices that break the model.
Edit: when I talk about a free lunch or a silver bullet, I am often thinking about the writing of Fred Brooks.
The only-ever-PHP coders I have known tend to be fairly polarized between fear of the unknown and the "grass is greener" attitude.
The ease of estimation thing was an aside, but I'm getting more convinced. With PHP there is only one way to do any feature: look up the library function, type it, refresh the page, and slowly accrete your functionality. With other languages there's some hope of a free lunch and it engages our tendency to optimism.