>By comparison, many other European countries (Germany, France, Sweden, Belgium, …) have specific types of legal entities for associations that have appropriate restrictions on what can be done with them. For example, they can generally not be sold, are required to be internally democratic with fixed statutes, usually (but not always) have open membership and an elected board. I think that would go a long way to fixing these recurrent issues.
As I understand it you can set all those things up in an American non-profit and many do in fact have that setup. So it's not a shortcoming of the legal system but of the people who created the entity. They chose not to do those things and no one objected strongly enough.