I disagree. You can spend 90% of your time doing e.g. data science, and then one day you need to integrate with a DB or make a cross-platform desktop GUI applic

I disagree. You can spend 90% of your time doing e.g. data science, and then one day you need to integrate with a DB or make a cross-platform desktop GUI application, as an example. Should you learn C++ (it takes a decade to become a very mediocre C++-developer), or Java to write a desktop GUI application? No, there isn't "always" a better choice for group 2. - Most software isn't CPU bound, so that defies "always" in your argument - You need libraries get things done What language would you always pick for group 2? Or would you pick a different one for each task, spending an order of magnitude more time learning them?