Or launder them by asking for big bills from the bank
Indeed it is wise to draw the biggest banknotes possible to reduce the tracking extent.
Note there is a trend of ATMs in recent years dispensing smaller max denominations. In Netherlands and France there are no longer ATMs that dispense banknotes bigger than €50. This is likely a move to increase surveillance without people realising.
That way you don’t have to believe the joke that data can’t be held more than 6 months.
Drawing big notes is orthoganol to the staleness of the data. You can do both. Draw big notes and also make the data stale.
It’s also not about data retention. It’s about data relevance. The more stale the data is, the less likely the source and destination are transacted by the same person. If you pull cash from the wall and that some day buy fertilizer with it, there is greater confidence that the same person is in both transactions than if there are months between the two transactions.