I think that's why it's hard for there to be a general consensus about how much is too little or too much laundry because every household is different, machines can be different, habits are different, climates are different, etc.
Absolutely. That's why I don't judge anyone for doing 21 loads of laundry a week when my family only does about 4. Maybe they all play sports, wear multiple outfits for their jobs, etc.
That also affects how we choose to do the laundry. For us, it's really not that big of a deal for one person to do all the week's laundry since it only takes a few hours on one day. But, if our family needed 3 loads to be done every day, I would absolutely insist that the each person did their own.
You leave dirty underwear and wet towels sitting for a week and a half?
Not the poster you quoted, but I only do laundry once every week to 10 days. Never had any problem with dirty underwear. And no one in my family has ever put a wet towel into a hamper-- they have known since they were toddlers that something wet will get moldy/mildewy.
Why is your husband throwing a fit? I agree that the kids' inability to use the hamper is a problem, but what's your husband's complaint about the quantity of laundry?
It's a waste of her time to wash clothes that are already clean. It's also extremely rude for the kids to expect her to pick up after them and purposely creating more work for her to do than is necessary. It's also a waste of resources. Sure, their family's finances won't be affected by the cost of water/gas/electricity to do a few extra loads of laundry, but they are still wasting water/gas/electricity by washing clean things due to the kids' laziness. Perhaps the husband is also bothered by that. Or maybe they have a septic system that can't handle the extra water of more laundry. All plenty of reasons for him to be upset in my opinion.
Personally, I would be annoyed if my husband was NOT upset over the laundry. The OP is obviously bothered by the issue, both their bathrooms are a disaster, the kids are being completely disrespectful of the OP's time and expecting her to do way more than is necessary because they are being lazy. If my husband was not upset over the situation, I would think that he also does not respect me or my time.
We had a similar problem for a very brief period of time with my oldest daughter. When she was about 8 she would try on tons of outfits every day picking out clothes for school. Because she was too lazy to put them back, she would just throw them on the floor in her closet. Then when she cleaned her room she would put ALL of the clean clothes in the laundry (dozens of outfits that would take multiple loads to wash). So basically instead of hanging the clothes up when she tried them on, she expected me to wash, fold, and put them away for her.
The measure of being a successful adult isn't just about intellectual accomplishments
I think this is why topics as mundane as how we do our family laundry receive some passionate responses. I believe most people are trying to raise their children to be successful adults who are productive members of society. But we all have different opinions about what that actually means and different methods of trying to reach that outcome.