I can tell an MBA guy to upload a CSV file and i'll take care of it. Imagine i tell him i need everything in a PARQUET file!!! I'm no longer a team player.
Do the same with a .CSV file and you'll have to teach those people how to use the .CSV importer in Excel and also how to set up the data types for each column etc. It's a non trivial problem that forces you down to a few million people.
.CSV is a niche format for inexperienced software developers.
Thanks
(I'm assuming the technical person can easily write a basic parsing script for the CSV data - which can flag, if not fix, most of the format problems.)
For a dataset of any size, my experience is that most of the time & effort goes into handling records which do not comply with the non-technical person's beliefs about their data. Which data came from (say) an old customer database - and between bugs in the db software, and abuse by frustrated, lazy, or just ill-trained CSR's, there are all sorts of "interesting" things, which need cleaning up.