its not that they wont have $433, it is that people will be unwilling to shell out $433 for two year old device, if they have an option to renew it for a shiny new model and roll forward into another BNPL loan
It is not rolled forward. If they don't want to pay the $433, then they don't. They return the device and the new device's lease doesn't include that $433.
It's not like a used car loan that some people have that keeps growing with each transaction (and at insane interest rates).