Well, to be fair to OP: small business and retailers are also not getting "real" money when they accept payment via credit cards from Visa/MasterCard.

To be honest I think the issue here is not due to speed of settlement, but layer-2 is not an acceptable substitute because it does not allow reversability. For the merchants it's good that they are getting the money right away, but most consumers will not dare to pay anything via layer-2 networks simply because they won't have any recourse in case they want to undo the transaction.