My mother is also a hoarder and does get defensive about her things too. The rule is for a hoarder's things is "Don't touch their things". My mother said the same thing about moving out if you don't like the situation.
The point is only if she is willing to get help, then and only then she will get help. Otherwise there is nothing you can do. My mother will also go out to the trash and bring stuff back into the house.
She was never fined or in the paper for having too much stuff though.
The only thing you can do is if she shows positive changes, encourage that and support her that way.
Read my posts of Why Hoarders Hoard, and How to help a Hoarder.
The only way a hoarder will change is if they change mentally and discover that they really want to change.
To them it's a lot of mental challenges, a feeling of security, fear of losing their security blanket. Also getting things makes them feel better even though they have no room to put new things.
I was planning on moving out until I lost my job, but now have to just deal again.