That's suggested often, and the obvious rebuttal is that CSV is intended to be easily edited and relatively human-friendly. The unit/record characters are not on most(all?) keyboards, so editing the file in a text editor becomes pretty much impossible.

As a counterpoint, nobody seems to be editing CSV files by hand any more. It appears at this point to be an interchange format between different spreadsheets, row-oriented databases, etc.

I promise they're still used by hand all the time, usually as a form of supplying data to a program in cases where a database is just too much. CSV is still a very common base for data-driven unit tests.