We have had night time temps here in So Cal this winter that have been brutal for us Southern Californians (40’s). If I was living outside in that, with the clothes that I normally have, I would be ‘huddling around a bonfire’ too :> 50 wont kill them, but it may take them some time to get used to it.
It was those brutal SoCal temps that were partially responsible for us leaving to cooler climes.
It is true, though; it is what you are used to that makes it ‘cold’ of ‘hot’...to an extent. With me, it is a damaged thalamus from extreme sunburn, thanks to falling asleep when & where I shouldn’t have. Anything over 75 & I start to sweat buckets.
OTOH, the Bible foretold of their discomfort: “Many are cold, but few are forzen.”