According to UniFi, my LG washer and dryer have each used 15.9MB in the last month. LG Dishwasher used 3.8MB.
I keep all IOT devices like these on client-isolated WiFi on their own VLAN with a speed limit of 250Kbps. They don’t have access to all the bandwidth they can eat, so they can’t participate meaningfully in a DDOS attack when compromised. 250Kbps is enough for “laundry is done” and “grill is pre-heated” push notifications to squeak through.