The main problem you will hit eventually is subtle bugs, like not handling CSV escaping correctly when, for example, the field value happens to contain a comma.

The main problem you will hit eventually is subtle bugs, like not handling CSV escaping correctly when, for example, the field value happens to contain a comma. Quick and dirty and probably fine for a quick PoC if that's what you're used to, but otherwise you're probably better off with a real language with libraries designed for what you're doing.