It does make you more immediately employable. In sum I agree, but why is the inverse never true? You can learn and use 2, since that is the advantage for employ

It does make you more immediately employable. In sum I agree, but why is the inverse never true? You can learn and use 2, since that is the advantage for employment, then use 3 when you need to just as easily. Let the tech live or die based on its actual merits (employment, technical etc), not trying to get more people onboard with propaganda. Considering the money is with 2, I think what you said backs it up even more. 3 will be easy to pickup when needed.