Brother accused of locking down third-party printer ink cartridges via forced firmware updates, removing older firmware versions from support portals [see comments]
I imagine they have some stupid note or sticker somewhere saying "to avoid damaging your printer only use genuine Brother replacement cartridges".
Then all they have to say is "we patched a bug where unverified 3rd party ink cartriges could erroneously be used and cause malfunction or damage to the product."
Plus, it's been universally understood that you have been able to use third-party cartridges. I really think if you're persistent enough, you'd get a refund in Australia. Because else (in Victoria at least) you could take them to VCAT for like $70, which will cost them wayyy more in lawyer expenses than the price of a refund.
This is not legal advice, but I reckon a refund under Australian Consumer Law is extremely doable if they go down this path (for existing printers).