Why Export Builder exists
The reason was practical: for a tax return we had to get data out of Craft Commerce in exactly the shape the bookkeeping needed. The standard export produced a file, but not the fixed selection, column names and order we reused every period.
A one-off script solves that month. The month after, the same work starts again. So we made the export itself a reusable part of Craft: compose it once, save it, and run it from then on without writing code again.