I get the impression that most (private) traders only want to... trade, just like pushing a button and then leaning back.

Programmers (or quant devs/researchers) have a completely different approach (and mindset!). They are the types who start with an idea/concept, build, test and modify it themselves (rinse and repeat...) before they actually apply it to real money (often months later). With an algo trading environment like Zorro you need to wear both hats.