Cloth diapers must be washed and boiled throughly to be hygienic.

This is certainly true if you are running a daycare, hospital, or similar. It's also true when diapers change ownership, for example when used ones are sold.

If you'll be putting them right back on the same kid, then no. Remember, you don't boil the kid's ass to be hygienic. You'll be putting that diaper on an unboiled ass. The diaper doesn't need to be boiled.

I think the hygiene aspect is about long-term accumulation of pathogens. You bathe the baby several times a week if not daily. Then you put on a cloth that has been exposed to many pathogens over X time. But I guess boiling shouldn't take a day, since we can pasteurize milk in a very short time.

You really don't need to boil cloth diapers, honestly.

Might depend on the age, I'd have a higher standard of sterilization for a newborn than for a 3yo.

Nonsense. Do you have kids? Kids have "blow-outs" all the time that send poop exploding out of the diaper and onto their pants and shirts (and socks...and shoes...). These clothes, they don't get boiled. We soak them in water and detergent for a few hours and then throw them in the washer with the rest of our laundry. I have two kids, including one in diapers, and I've never once had any hygiene issues and you better believe that my washer has seen some poop.

You, and probably several million (if not a billion or so) other human beings who have managed to do it well enough before nylon diapers came onto the scene...