I've said it before and I will say it again. It's not down to peoples' own expectations that our lifestyle now needs to be a certain way. It's down to more and more regulations, which are brought in by people who have no monetary worries, and expect ordinary people to comply.
I will give you a few examples:
Owning a smartphone and a laptop or PC at home is a must for most people these days. That's a huge amount of money to pay and maintain. Too many everyday things are based online now that are non-negotiable. Almost all bills are digital (and very few allow you to keep the option to have paper copies sent to you), so is most banking with more and more branches shutting on a weekly basis. Job applications, access to telephone numbers for companies (when did you last see a telephone book?), booking a doctor's appointment - you can do very few things without the need to be connected to the internet. Bus tickets are almost all digital where I live. Internet cafes from the 1990s and early 2000s are a thing of the past, most workplaces have a no-personal-use policy in place and libraries are open at such inconvenient times (if at all available in your neighbourhood) that you need internet access at home, which costs.
My 7-year-old smartphone still works fine, but I have had to buy a new one yesterday because the old phone cannot deal with storage demand for apps anymore, even when all non-essentials are already deleted off it. So that's £150 for a phone that will allow sufficient storage for apps for a few years before it, too, becomes obsolete. One app I need is for work - it is a non-negotiable to have this on my phone to be able to log into my system from home, and two-factor authentication is a huge thing for most portals now. That's government requirements for ever more security having us pay more for devices, phone contracts and internet access. Multiply that by however many children you have, because they will need these things for homework.
Cars are a must outside of large cities. Even in my large town, public transport is abysmal at the best of times. I cannot get to work on time by bus, because a 10-min car journey takes 2 hours on the bus, and that is if all are punctual (my eldest takes the bus to sixth form and is regularly late because the buses just do not turn up). Many employers cannot afford town centre rates, so offices are in the middle of nowhere, as are more and more shops. With the job market in a mess, you take what you can get, but that also means most working adults need their own car. Few have the privilege of working in vaguely similar directions. So if you see a household with more than one car, chances are they need them for work. And because time margins between work and schools/ childcare are often tight (owing to most childcare providers and schools only accepting people from within a certain radius of their home addresses), cars are, again, a must to get between one place and another in sufficient time to not be hit with huge fines for lateness.
Own rooms for children are becoming more and more of a must. There are legal limits for overcrowding, so where, 70 years ago, 2 children may have shared a bed, that would now be seen as unacceptable, as is usually a situation in which older siblings of opposite sexes share after a certain age. And as the children get older, housing costs often mean they cannot immediately move out, so need their own rooms as adults to get a modicum of privacy in their parental homes. Someone upthread mentioned separate bathrooms - I can tell you now that, with time pressures, it is almost impossible for all members of our family to be out of the house ready for work/ childcare and school without a second toilet facility - while one person is in the shower, the other brushes teeth. Cleaning your teeth in the same bathroom as your naked, showering parent is frowned upon, you see. That's a mixture of failed housing policies and what is seen as socially acceptable having shifted.
Now let's mention some legal costs - insulation regulations, boiler servicing regulations, electrical safety regulations, more and more things deemed unsafe for an MOT, higher taxes to comply with "green" targets, legal requirements to be insured for a number of different things just to keep a roof over your home or, in some cases, your job - and is it a wonder people are struggling?
We are not talking 3 foreign holidays a year; that divide is getting larger, too. But just living a normal life has become expensive and reliant on things that, years ago, would have been considered a luxury.