I've just read a DM article about William popping down to his local for a cider and a plate of chips dressed in his best M & S jumper. I am not a massive royalist, although I'd keep them in a vote, but I must say, he got this just right
William and Kate have an advantage in that they understand the British culture, and how best to walk the tightrope between appearing too privileged and out of touch, and hitting the right notes to come across as "one of us". One of the reasons I started to wonder about how well Meghan was being advised (or, ultimately, how much she was listening to any advice she was given) was because she seemed to consistently get this wrong. She didn't by any means always land on the "too privileged" side of the line (before the wedding for example she wore some M&S pieces, and wore jeans from a small Welsh company etc) but when she did, she really jumped into that space - her couture evening grown for her glamorous engagement photos, her $100,000 Dior caftan for her trip to Morocco, the penthouse suite baby shower in New York. She presumably wanted to enjoy the wealth, and access to the wealthy, that her new role gave her, without appreciating (or caring) that to do so hit the wrong notes in relation to the people who literally support the monarchy, and would need some careful work to make it clear that that she wasn't generally perceived as positioned on that side of the line.
And before anyone comes back with "But Kate..." I happily accept that Kate also wears some big ticket clothing items, but she generally does so at the kind of events where the public expect her to put on a show - State Dinners, Trooping the Colour, Ascot etc, and so they play entirely differently. And she is also really good at dialling it down often enough at the events in between to still seem in touch. And while I'm sure that her and William's regular holidays in in Mustique are massively expensive, having an annually holiday with your extended family in a beach resort is a normal enough thing to do for most of us that it doesn't come across as out of touch. Other royals are also really good at this - Crown Princess Victoria of Sweden regularly wears evening gowns from H&M, mixed with priceless jewels from the family vaults, for example.