In Stafford, all of the taxis I have used during the pandemic still only use cash. Yet the barbershop I use takes card no probs.
In the arcade, fruit machines still take cash. Penny pushers too, and surely there is no way around that?! Arcade games would be a bit easier because they take cash to play the game and don't give money back out. Quiz machines in pubs would still need to take cash because they (occasionally!) give money back out.
Fairground operators still only take cash. "Pay in the cash box for your next ride!!"
Coin-op rides like you see outside a supermarket could be converted to take card.
Coin-op vending machines are starting to take card, as with train tickets, pay and display / parking machines.
Someone up-thread mentioned car boot sales and that is still cash based.
Beggars take cash only, and sometimes food.
If I buy a takeaway for a few of us by card, then the others will pay me their bit in cash. Or otherwise we just take it in turns and we all pay by card each time.
Paying tip is still acceptable in some situations and that is always in cash.
So in summary:
Cash - still relevant
Card - still relevant
Cheques on the other hand - not relevant!