Almost nobody pays for anything with cash in the UK anymore.
I think this is an illusion.
Sure, if you're going into almost any shop it will accept other payment methods and most people will use them, particularly at the moment. Similarly, ordering anything online isn't likely to be cash-on-delivery.
However, there are still reasons people might need or prefer to pay or be paid in cash, only one of which is "I'm a dodgy tradesman evading tax". For example, we've used a few local services for things like cleaning or gardening. They often like to be paid in cash, at least for the first visit or two, so everyone immediately knows it's all above board. This is common IME even if they might be happy to be paid (or even prefer to be paid) electronically once they get to know you.
Is the use of cash declining here? Certainly. Is it negligible? Not even close. Is it still useful or even essential? Sometimes, yes.
Paying people in cash seems like the exact opposite of an indicator of everything being above board.
It's also a traditional sign of honesty, and a convenient way for someone who has provided very good service to be tipped without making a big deal of it ("Keep the change"), and both of those things can be important in these kinds of situations.
Well I accept your experience, but in my experience asking for cash is a traditional sign of dishonesty and tax evasion. Why do you think they always offer a hushed discount for cash?
A professional tradesman invoices after and then accepts a bank transfer. Asking for a wad of banknotes is grubby.
My favourite cheese shop used to only accept cash, but the owner retired. Beyond that, the only thing I need cash for is to give to homeless people. I think they're the main group losing out due to the switch to electronic payment; the can't afford the equipment for it.
Granted, I haven't been there in six months because of the virus, but I watch current British television every couple of days, and I still see people using cash.
>> Almost nobody pays for anything with cash in the UK anymore
Payment systems should be nationalised and run by a country's central bank. It's a very boring infrastructure equivalent to roads. There shouldn't be a private company taxing every single transaction someone makes. Do that and the small stores can drop the fees.
Sweden has a pilot project for a digtal currency: https://www.technologyreview.com/2020/02/20/906146/sweden-ri... , I wonder how it's going.
