This is no longer as common as it used to be, and besides chargebacks (plus fees) get passed to the merchant.

Chargebacks don't cost a payment network anything.

They keep the payment fee, and they charge you a large chargeback fee. They don't lose or spend any money out of their own pocket on it.

If you have high fraud rates, they charge you a higher per payment fee.

Our company is both a payment network and a merchant, depending on specific product lines and such. We spend a lot of time preventing credit card fraud on our merchant lines of business, and very little on our payment line of business, because chargebacks cost us nothing there.

As designed.

I can't believe people keep perpetuating this lie, that they very obviously haven't thought critically about. It's so frustrating. It's like everyone just repeating gormlessly that the sky is actually purple when they can just look at it.