CSV is human readable and writable, but that is only part of the advantage of CSV. Its simple format is great as an archival format. It's the plain text of data formats. Decades pass and you can still read it without much of an issue, though people are rightly pointing out that the format is ambiguous is nature and subject to a lot of interpretation. I've recently been compiling a lot of decades old experimental datasets, and it's honestly great when I find plain text files from the 1980s, since we can still read them! It's the more exotic data formats that came about later that are often more difficult to read properly.

The Library of Congress lists CSV files as one of its preferred formats for archival datasets: https://www.loc.gov/preservation/resources/rfs/data.html