Mind you, even relatively simple fridges can technically have firmware because these days the cheapest way to implement something like a defrost timer is with a microcontroller. Of course that firmware is so simple that it doesn't need updates and definitely doesn't need to be connected to the internet.

Other than that I don't really see what a smart fridge can do that you can't cover by sticking a cheap tablet on the fridge door. Sure, maybe a smart fridge can order butter from Amazon when it thinks that yours runs out but you can do the same with your phone and "buy it again" in seconds. Assuming that you even want to buy your groceries from an e-retailer.

It's definitely a pointless price inflation device that makes the fridge less reliable to boot.