Decades of advertising might have something to do with this. Plus the fact that hoarding money, houses, cars... is highly praised.
This is not at all like the type of hoarding that's described here. You're referencing essentially greed, which we've been told is good at least since the early 80's
What about the type of hoarders who collect stuff for monetary reasons? I don't think there are memories involved, and I don't see a direct emotional connection. It's just people who believe that someday this stuff is valuable, or the other side, it's something they might need some day, for repairing or building, or something like that.
Lets not forget non-trivial part of population is on spectrum of one/multiple psychiatric disorders, but say 2 out of 10 doesn't get you to mental asylum, rather on lifelong medicines if you get diagnosed properly, but most people do not get that luxury. So they often end up a massive pain in the A for basically everybody around them.
Yes, and the root cause for all of them is the increase in, and the inability to handle, oxidative stress:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10051630/#:~:te....
There’s likely a U-shaped curve regarding the benefits of exercise and mental health.
As someone who struggles with mental health issues, and frequently not getting enough of many of those things mentioned, I've worked to try to do better about some of that; and it can sometimes help a bit. But the whole "get more exercise, touch grass, see a friend" isn't the magic cure-all that some people make it out to be; and worrying about doing enough of it can become a stressor all on its own. Additionally, seeing them as the solution can sometimes lead to harmful obsessive behaviors of trying too hard to seek them out, at the expense of other things like work or family time.
Anyhow, not saying that getting more of these things is bad, or that they have no effect. Just that a lot of times discussions of mental health online feel very reductive. More exercise, more outdoor time, more time with friends, more antidepressants; each of these could potentially have positive effects, but they can also have negative effects, or be unobtainable, or there could be one of myriad other issues that need to be addressed, or there could be situations, either mental, physical, or social that are so broken that they can never really be addressed, just lived with or in some cases not even that.
Getting rid of items is like throwing away something specials d apart of oneself.
The rise of this mental disorder tracks the rise of all mental disorders in the west (eg. >60% of our communities girls HS volleyball team last year were on antidepressants). There are known microcauses for this: isolation, not enough physical activity, little vitamin D/Sun exposure, family structure, etc.