[deepsun]

Does it? I think it only affects when you enter the value, it doesn't change the underlying data that someone else stored in a doc.

[mulmen]

I just tested it. The setting applies on data entry but opening a CSV or similar delimited file counts as “data entry”. So if you work strictly with xlsx files you are fine but it will irreversibly convert the values on open for delimited files unless you change the defaults.