> In most businesses, programming language speed is NOT the bottleneck of the operation

You know, people love to say this, but in every company I've worked at (sample size 3), past the first year or so of operations, programming language / framework speed actually was a very significant concern for the business.

This may be self-selection; scaling and performance are two of my areas of specialization. However, whenever I'm on the job market, there doesn't seem to be any shortage of companies trying to hire people to help them handle their performance and scaling problems.