AFR article provides further insight: The move to regulate the...

AFR article provides further insight: The move to regulate the sector marks a key point in a lengthy process which began when the federal government in November released three options to overhaul how the BNPL industry operated.
a. Most stringent option - The most onerous option would have treated BNPL like credit cards and other loans requiring full credit act regulation. Backed by ASIC, Westpac and other banks (probably because they view BNPL as competition).
b. Middle option - The government has chosen the middle option, placing the sector in the Credit Act and applying a tailored version of responsible lending obligations, which will require providers to assess BNPL “is not unsuitable” for a customer. BNPL players will also be required to hold an Australian credit licence. The option selected by the government was supported by Zip and Commonwealth Bank, which has developed its own BNPL product. Zip already conducts upfront customer credit checks because it provides higher spending limits than Afterpay. (If Zip supports it, it was likely within their best interest out of the 3 options; minimize competition from smaller BNPL's, and continue business as usual)
c. Most lenient option - The least onerous of three options included amending the Credit Act to impose a requirement to check that a product was “not unaffordable” for a person before it is offered to them, plus self-regulation. Afterpay, meanwhile, was pushing for the first option, which essentially involved self-regulation.