> can still make a quite good career with only knowing one of them.
I think this is (at least partially) a side effect of the pedagogy of computer science in schools changing throughout the decades. When I was in school, just about the entire program stressed OOP, with very little focus on imperative/procedural programming. Newly minted programmers fresh out of school don't have the exposure/mindset to jump straight into one of these (C maybe being an exception). The old guard that called these languages home are a dying breed, and the salaries paid to program in them these days bears that out the scarcity that results.
I think this is (at least partially) a side effect of the pedagogy of computer science in schools changing throughout the decades. When I was in school, just about the entire program stressed OOP, with very little focus on imperative/procedural programming. Newly minted programmers fresh out of school don't have the exposure/mindset to jump straight into one of these (C maybe being an exception). The old guard that called these languages home are a dying breed, and the salaries paid to program in them these days bears that out the scarcity that results.