This is actually what happened with floppies. While people used them less and less, stores stopped selling them when companies stopped putting the drives in machines. Floppies were small and essentially useless, they needed to go away because there were better alternatives. If you kill DVD and Blu-Ray there will be no alternative. (As I argued above, flash drives are not an alternative.)
I wish someone would tell my company this, we still use floppies to send files in the post!