I think the seats are some how thermostatically controlled.
I think it might be dependent on outside temp or ratio of outside temp to inside temp.
Sometimes they put out a lot of heat and sometimes not.
But when it's really cold they seem toasty. But as you warm up, it seems to back off.
I think if you just ignore it, you will be comfortable and not end up with a sweaty butt and keep having to thermostatically control it manually.
I think the wheel does the same.
I think many of us are just used to it being full on (or full half on) or off.
It takes some getting used to. so many things to get used to