Yes, people are generally more miserable, but I have noticed that way before Covid hit.
I think people's attachment to social media plays a huge part, as does UK culture in general.
Social media makes us compare our lives to the seemingly perfect world others live in, and to their seemingly perfect skills.
So we feel a need to scrub every inch of our houses lest they look lived in, we feel the need to look like a Barbie doll with tons of make-up and new clothes all the time, we feel the need to work more and more hours to afford more and more goods because social media deem them necessary.
We are constantly striving for unachievable things. While that hasn't changed, the amount with which we're bombarded with what is unachievable for the majority of people has.
UK culture is centred around money.
In my home country, it is perfectly acceptable (and indeed often preferred) to invite people over to your home for a cup of coffee or a meal and some chill time. Here, there is a need to frequent pubs and cafes, which inevitably cost more.
Days out in my home country are usually inexpensive things, like walks in the countryside, a bike tour, parks, beaches, the odd church or other historical building. Theme parks, zoos, aquariums, water parks, expensive museums or historical sites etc. are annual things, if at all. People in the UK feel the need to spend so much money all the time.
Simple skills like DIY beyond putting flatpack together and any hand-crafted items are sneered at. Even hobbies have to be grand; I know so few people who do things on a small scale for the fun of it. You see it on here all the time for things like World Book Day (my child was one of two children in their year group with a homemade costume, all others were bought). Mumsnetters so often state they wouldn't like homemade "crap".
People would rather pay professionals than accept that they can do things, but they might not be Insta-worthy. So people have less money, then begrudge having to work more to afford this.
Simpler lives are much happier lives.
And it appears that happiness in general is not fashionable. So many people feel the need to tear down those who are happy to make themselves feel better. People filming themselves ranting about one thing or another get millions of views and followers for being "edgy".
Nah. I dance to my own tune. I am happy.