I am a hoarder by anyone’s standards. I don’t think many people realise as my house, whilst not remotely minimalist, is tidy, and I can always find what I am looking for.
But I have a huge amount of storage upstairs (fitted wardrobes, cupboards and drawers which were here when we moved in) and the type of attic which is in the eaves so is easy to get to (no need for ladders).
And that is where I hoard. I am way better in some ways than I was, but a lot worse in other ways.
I’ve made massive progress with kids stuff - I have thrown all old school exercise books, only keeping an a3 plastic envelope style folder (I think they’re called portfolio cases) of things that they’ve worked on or made per year. And labelled each of them eg Dc1 - year 2. I’ve thrown or donated all clothes, shoes etc that don’t fit them, save for a box of baby stuff which includes first sleep suit, hospital band, scan photo etc, and the cards we received when they were born.
I don’t keep any cards unless they’ve been made for them.
I have kept only small sentimental items eg their favourite soft toy when they were little. It’s all labelled in plastic boxes.
I’m ready to throw away all CDs and DVDs but DH is lent so we are hanging onto them.
My nemesis is toys and my clothes and my shoes. Toys because the DC can play with toys in different ways and I don’t want to throw things which they will otherwise come back to. My shoes because I currently have bunions which means I can’t wear 90% of them, but I will be able to if and when I have bunion surgery. My clothes are complex - I have wardrobes full of things that I’m eithe half a stone off fitting into, or maybe 3/4 of a stone from fitting into others, or a stone from fitting into the others. And these span all seasons. And there are lots of them. So I have lots and lots and I can’t seem to get rid of them. So they are still upstairs filling every wardrobe we have.
DH is a hoarder of books. He wouldn’t describe himself in these terms, but he will not part with a single book, and we have no space for more (possibly because of all my clothes!). And he still buys more. Wont have a kindle (I don’t like kindles either, but I will part with books that I bought 20 years ago and am never going to read again despite enjoying them at the time - thrillers etc).
I don’t have trauma in my childhood, but it is a genetic thing, I think. My grandmother was the same, but she also kept newspapers (the same thinking as you in relation to the Duke of Edinburgh) and things from WW2 and whatnot.
I agree with the ‘if you have space and it brings you joy, then keep it’ way of thinking. For example, I wouldn’t be able to let go of a collection of theatre programmes. It’s a collection. Not that I’d want to derail you!!