I'm very sympathetic to all of these concerns, at large. However, as things are done, many authors will make the most money by agreeing to this contract, and customers get the cheapest option there. The only people actually getting hurt, right now, are the other platforms. To paint this in any other way is not at all honest. And that is the part that is annoying me.
There is also a moral hazard "they will switch some day" argument to be made, i suppose. But I don't like hinging current practices on future hypotheticals. Making a choice today should be possible with the understanding that you can make a different choice in the future.