Almost no one I know in software development is using the language(s) they were taught in academia -- and I actually don't think most "real world" programming languages are good for teaching about programming fundamentals. When I did my BSc in (Math and) Comp Sci, we did a little assembler to learn about the machine level (and we studied different machine architectures), we did a tiny bit of BASIC in the first year just to support Math coursework, and a lot of Pascal over the three years, so we could learn about pointers and memory (stack vs heap) and data structures and algorithms, problem decomposition, and so on.
The University of Washington has a CS304 course available online as "Programming Languages" which teaches fundamentals of various styles of programming -- statically typed functional (Standard ML), dynamically typed functional (Racket), and dynamically typed object-oriented (Ruby), on the assumption that students will encounter plenty of the "fourth quadrant" (statically typed object-oriented) once they get out into the commercial world.
I learned about a dozen languages at university (in my spare time, for fun), and I've never used any of them commercially. Over my career, I've used about a dozen languages in production -- and I've had to learn new languages to stay employable (my arc was loosely COBOL -> C -> C++ ->
Java, with ColdFusion, Groovy, Scala, and Clojure since then, all on the JVM), and I've tried to follow the advice in "
The Pragmatic Programmer" to "learn a new programming language every year". It's a lofty goal and I've typically only managed one language every two years, but over the last decade I've played with Elm, Go, Rust, and Kotlin (and was only disappointed with Go). I think learning new programming languages generally improves your skill in your "home" language, because you get to look at problems in a different way.
At this point, the programming language space is pretty crowded -- and only likely to get more so, I suspect -- so being a polyglot just makes sense from a career point of view.