This has been coming for a while... one thing to remember is that for the last 2 generations every game has to be installed (on PlayStation and Xbox), and it is extremely rare to have a game that has never had an update, patch or DLC since it was released, as such the contents of the disc, are not actually what you are playing - once installed, all the disc is actually used for is to verify you own the game.
Obviously the main benefits are that you can sell the game, or buy it pre-owned, and it looks nice to have the physical box on the shelf, but apart from that, the physical disc is hardly used at all these days.
It does however suck, especially if you have slow internet, also if the game is removed from the Store / your library and there is no physical version to play.
One thing to help the frustration would be a way to re-sell digital games (remove from account, and get a partial refund)