Bidet (no hand sprayer, just a toilet seat based jet) works fine in this US household. I don’t notice the cold in the winter. Maybe I have an exceptionally robust asshole, but our water gets very cold in the winter.
Do you have decent central heating? Japanese households didn’t (and still don’t, it’s not required by law even in Tokyo), so heated toilet seats and heated water is considered essential. There is a reason kotatsus never caught in the states I guess. You won’t encounter nozzles in southern China either because the winters are too cold and they have even less heating than northern China (which is why everyone is wearing winter jackets indoors).
Even in the US, I can’t imagine installing a nozzle here in Seattle, but we also don’t have central heat (just a heat pump with remote units in a couple of rooms).
> we also don’t have central heat (just a heat pump
I'm so terminologically confused at this point by comments like this. In Texas, many people's central heat is a heat pump. My current house's heater is the first I've lived at in over forty years that wasn't a heat pump (this one is gas). High end homes, cheap rentals, everything in between, heat pump central heating.
Ductless heat pump (aka mini split) you need indoor units to serve each room that the heat pump handles. We have one in our master bedroom and in our open living room kitchen, but not on the bottom floor (kid bedroom/office, and our master bath really isn’t heated well by our master bedroom indoor unit, so it has a separate wall heater that doesn’t have a thermostat so we never use it. So our bathroom is a bit cold in the winter, although it’s Seattle so never really that cold, although my wife avoids the toilet for the one in the living room since it bothers her more.
So…is a ductless mini split heat pump supplemented by a bunch of resistive walk heaters, one gas fireplace, and no central thermostat really considered central heating?
In China, this becomes even more pronounced, northern cities provide central heating from heating plants…so central means “central” in a much stronger sense. Apartments are poorly insulated from each other so it makes little sense to heat each unit separately. In southern China (and lots of older Japanese housing), you don’t even have good insulation so all your heating is localized (eg via a kotatsu and heated toilet seat, or heated train seats which are really nice). That is a lot less centralized than a minisplit (which are catching on in southern China these days as well).
