People working outside of their comfort zones generally don't know all the answers. That goes both ways. I recently watched a desktop developer reach for a Java servlet because they didn't know Javascript.

I think thee is also definitely a problem where if you don't use the right/current fad/popular stack you'll have a lot of trouble hiring people to work on your stuff.

Especially true since front and back end web stuff is so huge and high paying. problem comes when those stacks are a very poor fit for the problem at hand. But sure you could get an old neck beard to write that in C++ instead of java/Ruby or Node.js. Great you only need a single core embedded processor and it doen't even get hot! And yeah then who's going to maintain it?