^It's a shame porridge is seen as posh. It's very cheap, very easy to cook provided you have either a hob or a microwave, you don't need to add anything but water (adding some milk is my preference but at a push just water is fine) and a bit of your sweetener of choice, it's healthy, it's warming and it's very filling.
But apparently it's demeaning, preachy and unrealistic and to expect desperate, hungry poor people to eat porridge.^
^^This.
Half the world, that are generally much worse off and spend a much higher percentage of their income on food than most people in the UK, live mostly on porridge, or a variant, or rice and beans or similar.
But anyone suggesting that people here should eat such a diet are widely derided and accused of being 'preachy and unrealistic', like Jamie Oliver or a conservative MP a few months back. These basic cheap nutritional foods are written off as apirational and middle class.
Jamie Oliver is widely attacked on here for trying to encourage people to cook and eat better - which is bonkers when it would lead to a much better quality of life for many people - instead of being overweight and ill on nutritionally deficient and expensive processed food, be healthier on cheap staples like porridge, pulses, grains and seasonal vegetables?
JO was criticised for citing Italian Peasants with their very cheap mussels and pasta - another cheap pasta dish upthread is also given as an example of a Labour Leader being out of step with his core voters - both pasta and mussels, or fettucine (sounds posh but is only a type of pasta FFS) with capers, tomatoes and olive oil) are very cheap, good food and quick and easy to cook.
It is obviously a very complex issue, but also appears to be almost unique to the UK (and possibly the US?), so the question would be, 'what is so fundamentally different about the UK to the rest of the world' and our attitude to food? The OP says she has lived in the UK for 10 years, so has clearly noticed a difference to where she lived before?
Someone upthread has mentioned the relentless advertising and pushing of shitty processed food. Maybe that's it?
It's not necessarily working hours - some people work long hours and still cook, some people work fewer hours and still 'don't have time to cook'.
Lots of things are cheap, quick and easy and don't require specialist equipment. OK you could argue that a microwave oven is - but how are people heating their ready meals? Slow cookers are cheap, use tiny amounts of energy and can be used to make cheap ingredients into a meal.
It could be that in the UK it is a lot easier to eat cheap food without needing to make any effort than it is elsewhere, where it is often simply not available or too expensive.
So some people have lost the ability to cook and don't see why they should make the effort when they don't have to and food only becomes and issue when people don't have the money to either buy good quality ready made food, or equipment to cook their own? Hence why it always comes back to poor people, with no-one criticising the better off person who can afford to eat at M&S and Pret?