At least 30% bombed writing a for loop and if statement though. And we let them pick any language they wanted, so that wasn't it.
I gave an open-book final exam that asked students to write a for loop on one of the questions. I would say around 20% bombed the question despite the very book sitting beside them having a chapter on looping. With examples.
After the class ended, I ultimately concluded a non-trivial number of students probably didn't do any of their own coding during the course. I'm pretty sure I have worked with at least two or three people in coding positions who couldn't actually code and relied on outside (spouse? out-sourced?) support.
Our screening was pretty good, so most (but not all) candidates could demonstrate one loop, but an unfortunate number couldn't do the nested loop. shrug