Of course ventilation works. It takes the moist air, OUTSIDE.
If the tenant wants the place at outside temp, then their breath will condense on the walls. Their problem, their cost when it turns mouldy, not the landlord's. Or the council's.
You don't need to be a Rigsby to expect your tenant not to behave like an animal. Unfortunately at the cheap end that's what you tend to get.
They always had somewhere to dry clothes in the bathroom, usually a 4 cord pull-out line. They got laminated information and instruction cards with local hospital etc stuff and prohibitions from drying clothes in any room except the bathroom.
I & mates had a few cases where a property was fine until the stupids moved in. Often due to having a crappy agent.
Draughtbuster vents low, and 100mm core-drilled vents high in the bathroom and kitchen and hall with fronts siliconed on, sorted them. Bathrooms need somewhere for the air to get in from the rest of the house, so the bottom of the door got a trim.
Better class properties and tenants, and pre-installed washer/dryers from a rental co also removed the problem. In one of the HMOs the vent had sticky tape over it and the results were showing - out she went, deposit docked.
Saying it's the landlord's responsibility to insulate, when the building construction won't allow it, are the dribblings of a dimwit nosenothing.
The tenant has to be responsibile for themselves.