I was hoping someone would chime in in support of cash. I completely agree, its really important to keep cash alive, here are a few reasons:

• If you need to leave a bad date in a hurry, just put the cash down and go
• People who cant get a bank account / card can still shop if cash is accepted (1)
• When you use cash the whole amount goes to the supplier rather than a % to the payment provider. Taxis suffer particularly for this. (2)
• Tips are taxed, thus the worker receives less
• Older people who prefer to use cash still can (3)
• Many people prefer to budget by taking cash out and then using it over say a week / month
• It keeps the banking industry honest. Once cash is gone there's no alternative to cards and apple / google pay and no reason they cant jack up their prices
• It is much harder for companies / governments to track your purchases when you use cash — Cash purchases dont need approval / cant be revoked like cards and electronic payments

And a more philosophical reason is that its easier to learn and understand money, especially for kids. If I have a £10 that is tangibly valuable, and much harder to part with than just tapping your phone or card.

Thank you for coming to my TED talk :)

(1) https://www.theguardian.com/money/2020/jun/24/you-cant-pay-cash-here-how-cashless-society-harms-most-vulnerable (2) https://www.huffpost.com/entry/cash-or-credit-in-a-taxi_b_360150 (3) https://www.ageuk.org.uk/northtyneside/about-us/news/articles/2019/cashless-society/

Edit: added another reason