What are the options for increased privacy in how you pay for things where you live?
Cash is the obvious answer, but what about buying stuff online?
UK here. Thinking of ditching cards/contactless for good old cash. No idea about online payments - not doing anything illegal so might persevere with cards for now. Zero experience with crypto.

They are. when I pay using a bank card many informations are shared with "partners". With cash I don't have to give my name to anyone.
You pull money from an ATM which scans the serials and associates them with you. You spend that bill at a shop which brings them to the bank at the end of the day where the serial is collected. So there is the information that you visited a particular shop at a particular day and bought something there.
This can be crosscorrelated with information from a dozen other sources. That information will practically never be used to your advantage.
Have you ever been on a cash based society, banknotes don't do bank - user - seller - bank route, sometimes it might happen okay but it's not the norm, these are global, not precise tracking.
I agree on this, but cash have still stronger anonymity and privacy than most electronic payment methods. That's why they want cash to disapear in favor of CBDCs and banking cards. That's also why corrupted european deputee have big bags of cash at home lol.