I suppose you could make the argument we do have to reverse arrays, but strings? Give me a break, only idiot programmers spend their time practicing for useless programming interview questions.
Reversing a string takes 2 minutes or less even if all you know is how to work with strings and how to write a for-loop.
Is reversing a string something I do in the real world? Very very rarely if ever. But it's not meant to be a question that simulates a real world coding problem. The point is that it's a very simple problem that anyone proficient in almost any coding language should be able to do. And I don't know anyone I've worked with who wouldn't be able to do this in 5 minutes or less, with or without practice.