I can definitely see the downside of lukewarm water
I never got to enjoy the rugger bath but these days I go to Germany where they have Therme with massive hot pools. Many are naked only so I have had my fair of bathing fun
Last month I visited 1 in
Sinsheim where a group of volunteer firemen were on a Stag weekend. We sat in the open-air bar, warm water up to our chests laughing and drinking for an hour or so - everyone naked of course. They were all pissed and it was only mid-day