There is a difference between the cheapest printer you can buy and the cheapest one you can own. Retailers can sort by the price at checkout; ownership cost also depends on how much ink or toner your printing uses.
The shelf-price order barely matters
A printer with a low purchase price can still land near the expensive end of a five-year comparison when every replacement cartridge or toner set is counted. The reverse can also happen: a machine that looks expensive on day one can recover that difference through much cheaper supplies.
That does not make the cheaper-to-buy machines bad products. It means they are being asked to serve a high-volume scenario where their consumable model matters far more than the initial hardware price.
Why the scenario matters
Two thousand pages a month is a genuine small-office workload. A household printing a few forms and school letters would see a different ranking because the supply cost has less time to overtake the purchase price. There is no one permanently cheapest printer; there is only the cheapest verified suitable printer for a stated pattern of use.