Besides its IT value, I guess it teaches precision and accuracy in problem-solving and logical thinking, and how to approach problems. But Maths, Science, Geography, Design & Technology, Art and Music can also cultivate those sort of skills, and of course IT overlaps into those subjects as well.
If it is available as an after-school activity, then it can't do any harm to give it a try, but I think it is possible it has been boosted and 'sold' more than it really deserves. The Raspberry Pi and other similar systems CAN teach the basics of IT and coding at a very low cost, but it will need a lot of effort and dedication, and good maths or physics skills as well, to make real progress. Also Lego Technic has computer-based activities, and some schools use that type of approach.
Accuracy and attention to detail are the main requirements to learn coding, but I think good employment opportunities should exist if all the other subjects are learnt to a high level. The ability to USE computers effectively comes into EVERY walk of life today, but that doesn't necessarily mean you have to know how to build or 'code' them.