where are you line drying them? In your bathroom, most people are lucky if they have an outside space to do this when living paycheck to paycheck
Honestly, there is an epidemic of self defeatist in our day and age.
Mold thrives in moist, dark places, not most sunny ones.
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.
Edit - and having lived in both, you're much better off drying things in a hot humid place than in colder ones.
But damn, finding used diapers in the toilet is annoying. Plus wet diapers hanging all over to dry. If it's your kid, though, it's not a big deal.