Programming language knowledge overlaps with skills in that different languages affect the ways you think about problems, but knowledge, skills and intelligence are different things.
Only having knowledge is probably the hardest place to be, and those are the least desired staff ("paper $CERTIFICATION"), but if you have the others then knowledge is (arguably) the easiest thing to add.
If you have programming skills then you can extend from that base into front end, back end, etc. It's going to be harder to jump to sales, because you don't have the skills or the knowledge. Similarly if you've only ever done sales, or accounting, or cooking, or whatever then it'll be harder to develop the skills and knowledge for programming.
Only having knowledge is probably the hardest place to be, and those are the least desired staff ("paper $CERTIFICATION"), but if you have the others then knowledge is (arguably) the easiest thing to add.
If you have programming skills then you can extend from that base into front end, back end, etc. It's going to be harder to jump to sales, because you don't have the skills or the knowledge. Similarly if you've only ever done sales, or accounting, or cooking, or whatever then it'll be harder to develop the skills and knowledge for programming.