The number that matters: 68%
The UK regulator projects lenders will lose about £1.4bn under the new rules, and merchants roughly another £1.4bn. Most of the lender loss comes from fewer transactions, not compliance.
Merchants pay the fee (typically 2–8%) only because shoppers choose BNPL. The chain runs consumer → volume → merchant fees, and the consumer is the first domino.
The US points the same way without regulation: card installment plans are used by 33% of Americans versus 14% for BNPL, and in one year card installments grew 43% while BNPL slipped 7%.