The WHO recommended a minimum indoor temp of 18º C (and a max of 24º C) for health purposes (and assuming appropriate clothing) back in 1987 (and they still stand by the lower bound, though the upper is locale dependent - e.g., 21-22º in Boston vs 30º in Thailand), so I’m not surprised that dipping below that is unpleasant.
Where I live 26ºC is a cool day, when an AC is on 17ºC I’m trembling and smacking teeth.
The WHO recommended a minimum indoor temp of 18º C (and a max of 24º C) for health purposes (and assuming appropriate clothing) back in 1987 (and they still stand by the lower bound, though the upper is locale dependent - e.g., 21-22º in Boston vs 30º in Thailand), so I’m not surprised that dipping below that is unpleasant.