So I personally just don't see the benefit from a less generalised version of coreutil tools
... but fair does I'm sure there are plenty who have use for a more specific tool.
Others have pointed out specific examples, but the general reason (which I don't think I've seen explicitly articulated) is that CSV isn't strictly line oriented -- for intsance, records can span multiple "physical" lines, because line breaks within quoted strings are part of the field value, not separate records -- so line-oriented tools don't work with CSV generally (they may if you happen to have CSV where nothing inconsistent with a line-oriented view happens to be done, but that's luck not something that is generally true of CSV.)
It also became super simple to extract and munge data with options for tabular data. With two tiny commands I can exclude rows, include rows, sed columns, merge tables, and export new tables, all with just csv files. So it's pretty handy.