Not sure what your basing that claim on. It is a natively supported format, even amidst its inconsistencies, and has been for decades.

Are you referring to a particular format variant?

Excel definitely opens CSV files, and Windows file associations tend to set that up by default. However, Excel then goes ahead with changing the content to often wrongly-assumed formats. My favourite hate is how it will convert mobile numbers from a string of digits to an unusable exponential-format number. Hey, it doesn't even set column widths to make the content visible!

You should use power query to load csvs into excel that way you can control the parsing of columns.

If Jane from accounting and Bobby from marketing know those trick (and they do) then Csv does open in excel, and its replacement has to do at least as good.

Just curious - what tricks are required? localc opens csv without an issue.