My vote goes to most day coders being Java people.
My coworker across the hall can't see why anybody would write Python if Java is an option. "Ooh yeah, let me at it in Java... I'll have a JSR-4567-compliant Bean to drop into a custom container in no time!"
You have to ask ask yourself, "why's that so" ? Why the so called day coders do Java, C# or COBOL and not Smalltalk, LISP or Ruby ? There's a reason for everything and in programming the reason to use language a instead of language b in a software "factory" is definitely effectivity. That is, how fast a product can be done using Java/C# or lisp ? How much is it gonna cost to maintain that product and add features ? How much is it going to cost to train new people ? And so on.
Those economists in management surely don't wake up one day and announce : "We will use C#".
The day coders pick Java/C#/Cobol because that's where the jobs are. Companies might have chosen them for sound technical reasons (or not), but day coders won't learn languages/tools that don't pay the bills.
For reference, a Monster search for .net jobs in Chicago gives 266 results. Java gives 403. Lisp gives 22 for the entire country. Not something to learn if you just want a job to fund your real life.
Management is persuaded by smooth-talking consultants looking to win more project hours, not by measured effectiveness. (I'm talking about industry overall, not anybody in particular.)
My coworker across the hall can't see why anybody would write Python if Java is an option. "Ooh yeah, let me at it in Java... I'll have a JSR-4567-compliant Bean to drop into a custom container in no time!"