They are mostly still around because you can't take Excel or smartphones into exams.

But quite frankly they are handy to have around if you want to do a trivial analysis or find some roots. And the recentish ones have input methodologies and functionality that is not present on any smartphone app.

Still my go-to for "I need to get an answer to a problem quickly". I dabble with electronics regularly and they are very handy for that too.