The other advantage not being discussed here is that once you have a csv parser, it can be trivially generalized to use any character as a delimiter, and you can usually find a character that isn't found in the data you're working with unless you're working with binary data. I work on a legacy system where passing delimited files around is usually the integration method of the day, and if you can't delimit with commas (common) then you just delimit with tabs. If you can't delimit with tabs or commas, then delimit with pipes, which are rarely if ever used outside of code. Or use tildes, or grave accents, or...
Doing this avoids quoting, which avoids an entire class of problems. And yes, if you're passing multi-megabyte files around on a regular basis, or transferring giant blobs of text or binary data, or looking for a storage format with metadata then csvs are an absolutely awful choice, but as with any problem you pick the right tool for the job, and csvs are a great tool when you want to easily move some structured alphanumeric data around in a format that's trivial to parse in any language and widely supported.
>it can be trivially generalized to use any character as a delimiter
But then you have the additional problem of trying to work out what the delimiter is. You can take an educated guess, but this isn't going to be 100% reliable.
This comes back to "picking the right tool for the job". If you're ingesting csvs/tsvs, you're expecting a given format anyway. If you expect the wrong delimiter, the worst thing that happens is you detect that the file has the wrong number of columns and fail out. Even if you're using a more structured format, if you ingest a file containing the wrong dataset, your process will still fail because the correct fields aren't there. No matter what your format is, you can't recover from somebody sending you the wrong file.
Doing this avoids quoting, which avoids an entire class of problems. And yes, if you're passing multi-megabyte files around on a regular basis, or transferring giant blobs of text or binary data, or looking for a storage format with metadata then csvs are an absolutely awful choice, but as with any problem you pick the right tool for the job, and csvs are a great tool when you want to easily move some structured alphanumeric data around in a format that's trivial to parse in any language and widely supported.