I'm not sure it's a trend as such, just people doing what feels right to them and not buying into consumerism when it doesn't interest them.
To me a car is a tool that I need because it saves me time compared with public transport and gives me access to my main interest, which is hiking in the countryside, visiting the beach etc. I drive a car that suits my needs and it won't occur to me to change it until it starts to become old and worn out because shopping for cars is a boring chore only done when absolutely necessary. Likewise changing furniture and decorating the house for the sake of it.
My current car is a 5 YO city car that I've had for 3 years and won't change for another 5-10 years, it cost £8k which is the most expensive car I've ever had but will work out inexpensive over time (I've done years of shit cars that broke down and left me stranded/stuck on public transport because it was all I could afford) so it's worth it to me.
But if I didn't have that money saved, I wouldn't have spent that much on a car and I probably mainly had money saved because I spend little or nothing day to day on the things that a lot of people spend a lot of money on - many people fritter hundreds of pounds a month on not very much, meaning they never have any money, because they've spent it. Even a couple of hundreds of pounds a month is thousands a year or tens of thousands a decade, just on pointless shit in a lot of cases (we are not talking about the people who's income doesn't cover the basics, but the middle majority, who have some disposable income but not enough so they never have to think about what they're spending).
Anyone who equates wealth with possessions would probably decide I was poor because I don't really have any overt displays of wealth, don't spend money on appearances and don't show off about holidays on social media. Yet it's quite the opposite, meaning I can afford to work part time, because I just don't spend a lot of money. Remember Fight Club - 'we work jobs we hate, to buy things we don’t need, to impress people we don’t like'. Some people prefer to do the opposite to that. Spend less on stuff, don't worry about what other people do/think and you have the freedom to work less/retire earlier.