20C in wintertime is quite cool for North America, in my opinion. I think 23C is commonly considered "comfortable," but obviously that will vary significantly by individual.
Wow. Obviously there are humidity differences during different seasons, but 23°C is probably the limit of "this is uncomfortably warm" for me if I set my thermostat above that.
Me too, but my husband and guests are clearly uncomfortably cold at my preferred 66/67, and my sister with poor circulation just about has her hands go numb.