In my opinion, a true Hoarder is a person with a mental issue that does not allow them to throw anything away....
A true Hoarder isn't able to let it go. They see value in every single thing that they have. ...
Had a family member, who along with two other couples, bought a parcel of land and subdivided it.
They were all friends.
We went to visit one year for an annual get together. This one couple, call them Couple A, had brought salsa and chips to the get together. At the end of the party, the salsa and chips were all gone, and a person was going to throw away the empty jar and bag. The Couple A lady who had brought the food was really rude and nasty about keeping an empty jar and bag of chips.

Right after Couple A had built their house, our family member went over to visit and the house was already full of stuff, disorderly, dirty and smelly. Couple A had cats and were letting the cats just run all over the place peeing and pooping. They would leave out food which the cats would eat, walk over, sit on, etc... They were hoarding cats in a brand new house. When Couple A brought food to a get together, we would only eat packaged food that was opened in our presence...
The husband of Couple A would collect junk and leave it in the yard. Placed looked like junk yard.... Not sure what happened to him but his wife was put into a mental hospital.
The husband of Couple B who had bought into the parcel, died of a brain cancer and eventually, the wife moved away. The person who bought Couple B's home ended up hoarding animals and not taking care of them. This person went off into the weeds and poisoned our family member's dog.
Our family member's spouse horded cats but kept them outside. It was a mess with the number of cats, cat crap, and the inbreeding. The spouse also had mental illness.
Another part of the family has a farm. Almost anything of value gets kept.

Even if it has all but useless. They have the barn space so it gets "saved" because somebody might want a 50 year of range. Or old mattress that has been kept in a barn full of mice... Going to be a mess to clean up.
Later,
Dan