I realise Catherine isn't a petty, vengeful person so it will never happen, but I'd love to see her flex her position by flaunting jewellery that Diana wore, which Meghan will never have access to. It would send a certain message...
I think it was discussed on @DaisyDooley royal jewellery thread, I may be wrong, but it is believed that certain iconic pieces that Diana wore were wedding gifts and as such have been retained by the crown and presumably are hidden away in the Buckingham Palace vault. I think we can be sure if Meghan had acquired any of those big pieces we would have seen the evidence.
I can quite understand why Catherine chooses not to wear these items, no doubt anyway it's not her style, but also she will be aware of endless tedious articles about "sweet nods to Diana" and she will also be respectful of how William might feel about it.
But with Earl Spencer's book, rumours of a H&M 30th anniversary Netflix special, and the final insult, the two of them rocking up back on the doorstep, now would be a great time to pull rank and wear those pieces.
"One of the most famous examples of Diana’s “lost” jewels is the extravagant Crescent set, a bold, modern suite of diamonds and sapphires given to her by the Sultan of Oman." This piece and the huge sapphire choker need the dust brushing off. Now is the time.
www.vanityfair.com/story/what-happened-to-princess-dianas-most-famous-jewels?srsltid=AfmBOopsxwWknnJpTL1rNUpDh-l2FpPEXYXLiUOvwPcjeRaWXuqGpLiN