At least with my HL-1112 (bottom-barrel model in 2015) and MFC-L2700DW (entry level all-in-one with decent, albeit aftermarket, multiplatform support) it's trivial to manually reset the levels once you know the button sequence - don't even need a retail cartridge with the mechanical "unused toner" spinner!

That said... yeah, who knows what they're up to, 5 years later?