This is a common misconception. You do have 240V(or 208V in some apartments if we're being pedantic). You primarily use it in the kitchen(range receptacle), laundry, and for your HVAC equipment or an EV charger if you have one.

Someone who knows what they're doing can also add a 240V outlet to any room.

We don't serve 120V to homes, we take 240V and split it. In fact, that's not the only time you use a mix of different voltages. You take that 120V, and then further transform it to 18-24V for things like doorbells and thermostats, or you use a power-brick at the wall to convert it to direct current to charge your laptop, phone, and other items. In none of those use cases would 240V really change your life. It's really only better at boiling water in counter-top kettles. I'm guessing we don't use more 240V kettles because we're not a tea drinking country and culturally people tend to use coffee machines that are "fast enough", but not slow enough to be worth switching over.