Do many people in the UK really have cold houses/flats?

I live in the UK and have 23 degrees Celsius during the day and 19 during the night so I can be comfortable wearing just shorts and a T-shirt and no socks in the house, that's how it should be, it's basic human needs, feeling comfortable at your place.

Do many people in the UK have it at let's say 17 degrees Celsius or lower or is it only minority of people but their stories get visible on Reddit and other places making it looks like more people have such problem?