I know it's written on Anapedia:
Date format for Grid export layout is MMM YY while Tabular Single Column is YYYY-MM.
Because, this helps in filtering data in columns. YYYY-MM format data can be filtered easily. In Grid view, time will be considered as Headers. Hence, time format is MMM YY
Thanks - it gives some insight to why. In terms of filtering on Excel after export, I would imagine both can be filtered easily.
Moreover, if Anaplan can choose what date format we are importing from a .csv file, why can't we choose what date format we are exporting to a .csv file? Or even specify something as date formats before we export?