And everything you just listed is supposed to be a GUARANTEE. What are you not getting by the fact that when you purchase a ticket, you are not GUARANTEED to be on that flight. There are zero GUARANTEES in the airline industry. Read the fine print of those "contracts" when you buy a ticket.
I'm not disagreeing that something needs to be done about it. The only thing I see being done about it though is the airlines charging you another $100 to "guarantee" that you will not be bumped off the flight. They cannot stop their business and potentially delay hundreds to thousands of other customers, all because of one customer.