Lists baffle me... I never did them, my kids have never done them and I just don't get it, it strikes me rude and entitled (even more so when it's adults doing them).
when my DS was 11 he announced verbally at dinner one day he would like the brand new (about to be released back then) Iphone for Xmas.
I think the response of everyone laughing was his very clear answer to that (he already has a £500+ Samsung phone that he NEVER uses and the matching smartwatch, speaker dock thing and other accessories) turns out it's only because kids at school were bragging that they asked for one, he didn't even really want anything like that he just wanted to 'keep up' with what the other kids were doing.
If my kid ever did do a list I would not bow and break to buying stupid things... I would pick one, I googled the mini speakers on this list and looks like they're £20 so I and would maybe pick something like that.
I actually don't find the diamond request crazy, diamonds don't HAVE to cost the earth... I was gifted a diamond tennis bracelet and earrings not much older but they're no fun, they just sit in the safe, certainly arent rocking diamonds to school or to show your friends.