Can't speak for OP particularly, but many newer houses in the US have the toilet in its own small room separate from the rest of the bathroom where the sinks, shower, and soaker tub are.

Though in my household I can say the door to the small room rarely gets closed and I can't convince anyone else to put the damn lid down. Until slurp-slurp-slurp the dog starts drinking it, in which case there's a "stop drinking from the bowl!" followed by closing the lid. I'm not bitter. I try to choose my battles, and "turn the fan on when you poop" is a hill more worthy of dying on. Still haven't really succeeded with the kids yet.

> Can't speak for OP particularly, but many newer houses in the US have the toilet in its own small room separate from the rest of the bathroom where the sinks, shower, and soaker tub are.

I hate this type of setup, because it means I have to walk to another room before I can properly wash. Then again, I believe many people only use toilet paper in the US, so they are probably used to it..

> turn the fan on when you poop

Windows also work well.

A window might blow air out, but it also might blow air in. This would result in drawing your bathroom air deeper into the house instead of exiting it. A proper vent fan will undoubtedly move the air outside.

> A proper vent fan

I don't think I have ever, in my life, been in a bathroom with a "proper" vent fan. AFAICT by observation, regulations must require a fan that makes seems to only make "chugchugchug" noises while seemingly doing nothing to the air.

Lots of vent fans in houses tend to not actually vent anywhere, or they're covered up with insulation. I know I had to dig my vent fans out when I moved into my house. Uncovering them led them to be much quieter and actually exhaust from the bathroom.

Good bathroom ventilation is important. Controlling humidity is a big thing, but also properly ventilating things like acetone or hairspray or other things along with bad odors is important.

> Lots of vent fans in houses tend to not actually vent anywhere, or they're covered up with insulation.

I do a lot of house repairs. I don't think I've ever seen a bathroom fan that goes outside except in mobile homes. They just vent into the attic. Same with many kitchen fans. They should all go to the outside otherwise they could cause moisture issues in the future.

In the water closet, of course.