How about having some repercussions when the airlines fail to deliver as promised. If I want to change a ticket it costs me $150 plus the difference in airfare. How about it costing the airpine when they fail.
no one forces you to buy other than fully refundable. Suck it up and pay for it if that is what you prefer.
They over book, don't have any spare capacity and when they have problems they cannot accommodate the passengers in their system.
you still cannot grasp the business model they must adhere to in order to make a profit and stay in business. They must have full seats. That is how they must operate, otherwise, the cost per ticket will be higher for everybody.
They cannot guarantee a seat. If you want that, don't fly or hire a private plane.
These airlines are not awash in money. Many have been bankrupt. Squeezing profits from a notoriously unprofitable business forces them to adapt ways to stay in business.