A lot of merchants have had the ability to let people pay for purchases using ACH payments.
that's what you get for not reading the story.
This makes it a bit more 'instant' but I am going to make the assumption that higher priced items will still have a delay between the order and the ship to make certain that the funds are there.
it seems like you are just making assumptions.
The world’s largest retailer has offered pay-by-bank through Walmart Pay since earlier this year. Until now, the transactions were akin to digital checks and took roughly three days to finalize when being processed through The Automated Clearing House, the same network often used for bill payments or paycheck deposits. Soon, customers opting for pay-by-bank transactions will see the purchase reflected in their bank account balance instantly – and Walmart will receive the funds immediately.
nothing beats instant not even bitcoin...and not only instant but instantly in your bank account so you can actually use the money. unlike bitcoin where you have to sell it to usd paying a fee then put in a withdrawal with some 3rd party and wait days to see if they send it to you or not.