That's exactly the problem. Why convert anything, especially if it's as lossy as CSVs are? You lose nesting and the rest of your structure in favor of a single header row. That's not a benefit.
If your real data is in JSON (and in JS/TS apps, it always is at runtime as only JSON objects exist in that language) it makes no sense to ever convert it, period.
Besides, corporate report type CSVs that are in training materials don't have data shapes anything like JSON or even most businesses software. You're crippling an established and useful data carrier in order to save pennies on tokens. Tokens are getting cheaper, so it's the wrong optimization.
If your real data is in JSON (and in JS/TS apps, it always is at runtime as only JSON objects exist in that language) it makes no sense to ever convert it, period.
Besides, corporate report type CSVs that are in training materials don't have data shapes anything like JSON or even most businesses software. You're crippling an established and useful data carrier in order to save pennies on tokens. Tokens are getting cheaper, so it's the wrong optimization.