This is true in many fields. In part due to education or culture, but also because people need compartmentalize things. For instance, as an illustrator it is ha

This is true in many fields. In part due to education or culture, but also because people need compartmentalize things. For instance, as an illustrator it is harder to sell your services if you are able to work in different styles. And yet this is what makes you more rounded and more resilient as a professional in the face of change. I imagine the same applies to a person who can code in different languages. A client will likely prefer the best in any given field. Someone who masters a single, proven way over someone who tries new ways or different techniques. And you can hone that single skill all your life. But as a practitioner, it might not be the best strategy. What do you do when your speciality becomes out of trend or obsolete? In the end, whichever school you pick, only the results matter.