My mother was a hoarder, she was a wartime evacuee, she lost her sister in tragic circs as they say in the early 1960s... trauma is an odd thing, I don't think it's always merit- or scale-based, it's as much to do with not processing it and thus being able to move on. Repressed or shy people therefore may suffer more from it? I don't know.
It spoiled our upbringing because we could never host. It's a bit like the difference between being morbidly obese and quite overweight, with the former you don't want anyone to see you but with the latter you don't either however, so it's broadly the same. Same issues behind it, very possibly, the feeling that 'more is more'.
Stops you living in the present of course, but if the last time you lived in the present you experienced that trauma, well, you want to live anywhere but there.
The rows I had as a teenager and beyond, the red mist would descend. Nothing changed. It seemed unique but of course you don't get invited to other houses like that so you don't know it isn't. The big win of the internet and threads like this is the insight it gives into other people's problems.
On a side note, in spite of this do label up the old photos and photo albums if you get a chance to, I didn't do this with Dad's old photos and he died last October, well, the last two years he had a bit of dementia so would not have recalled them but... no excuse for not doing really before. Now we have a drawer of 'dead' photos, it could be someone else's family. It's not all like that but too much of it is, shame.
Seems I've inherited a bit of the hoarder thing, though. The stuff gets on top of you, you can't out stare it, I've learned! But you end up carrying the past with you and that is a burden. You can't be happy in the past or the future, only in the present.