Right. That's why we have technology and other advanced things, to live like cavemen used to.
Not everybody lives at the right latitude to have 22 degrees Celsius indoors without additional heating in the winter.
That being said, as someone else said, controlling humidity is also a concern for the long-term viability of buildings.
17 at night, 19.5 during the day is as hot as our house has ever been in winter; though with a new baby I suspect that might change by 0.5 for a while.
I'm currently happy at 18, it's pretty nice if you're a bit active.
Where did i say or imply any of that?