My washing machine has wi-fi. I didn't buy it for that reason, but it just happens to. Using the app, I have some programme options that aren't possible to select using the hardware dials. I can do things like change the detergent dosage and the number of additional rinse cycles. It has some "special" programmes for various specific fabrics. And it has things like maintenance diagnostics and the ability to run a specific self-cleaning cycle.
That's all pretty useful.
And what's the actual danger of connecting it to wi-fi? Will Big Data know how often I wash my towels? Do I need to worry about the government spying on my fabric softener usage? Will hackers seize control of my machine and ransom my ability to get clean underwear?
I just can't see the big downside here (other than the fact that the machine is more complicated than it needs to be, but that ship has already sailed seeing as I already own it).