I do think some of the issues around cleanliness is to do with depression but also sometimes a lack of knowledge.
Like @DontWasteMyTime I was brought up in what you would term as real poverty, in the 1960s/early 1970s in my case.
The difference between then and now is that those who had a bit more in a community didn't have a LOT more. 'They' may have had central heating or an indoor loo, neither of which we had along with no hot water tap nor any form of heating in the bedrooms. But they still only had a holiday at the coast for a week. Not a three week trip to Disneyworld or whatever. And we also had a week to the seaside if mum or dad got a bonus or saved a bit.
And, without social media, we barely knew about what they had. Depression existed, of course it did, but everyone was in the same boat so you didn't see an insurmountable mountain to climb all the time.
Most of my friends lived the same way as we did so we knew no better. When everyone is living the same way you assume that's normal. Which is why you often hear older people saying 'but we were happy' - looking back I have no idea how we could have been happy but I don't look back at my childhood and feel hard done by.
We had clean clothes every day. Sometimes we'd wear something, air it for a few days then re wear it because we didn't get sweaty like adults. Underwear was fresh on every day without fail. Dad shone our shoes every Sunday evening.
Mum and Dad would often hand washed their blouses or shirts at night, pop them on the fireguard and get them dry in between full laundry wash. Laundry day was always on a Saturday as both mum and dad worked full time - as did most of my friends parents, both wages were needed to keep the wolf from the door so, like today, they were short on time.
But another key thing missing nowadays is that we were also taught domestic science (as they called it) at school. That involved hand washing clothes, scrubbing the collar, armpits and cuffs of a blouse or shirt to get it clean, as well as polishing or cleaning furniture, budgeting and cooking. And yes, even in the 1970s, the boys in my class were taught the same.
I don't know of many schools that even do cookery lessons now and even DS's school (which does for just 6 weeks a year), they certainly don't teach laundry or how to clean things etc. The assumption is everyone has a washing machine. Which is fine, until you don't have a washing machine or the oven breaks down or the microwave goes on the blink.