[flukus]

How do you think people washed and dried clothes there 100 years ago? How do you think they do it in more humid and poorer places today? Do you leave your towel on the towel rack and let it dry there or do you throw it in the dryer every time?

Mold thrives in moist, dark places, not most sunny ones.

[romwell]

A 100 years ago housekeeping was a full-time job, and quality of life was generally pretty bad.

Also the society functioned differently; one middle-class salary could sustain a middle-class family, for one.

We no longer live in that reality, nor would anyone want to.

It's like saying that homeless people are OK because there were no buildings in prehistoric times.

[flukus]

Neither societal structure or quality of life affect the drying time of cloth diapers in humid places.

Edit - and having lived in both, you're much better off drying things in a hot humid place than in colder ones.

[NoGravitas]

We used cloth diapers in a place that's hot and humid but seasonally cold (the US Deep South). Outside on the line, diapers dried a lot faster in the summer than the winter. We ended up having to buy a used dryer for winter use, because they simply didn't dry fast enough to be ready by the time we needed them.