PS 5 will release in holiday season of 2020. Mostly during Xmas time. Sports franchises will move to PS 5. Most of the gaming companies will stop making games on PS 4 after nextgen console arrives. Slowly after 3-5 years they will stop support for PS 4. But you can buy all those awesome games which were released for PS 4 like Uncharted, Bloodborne, God of war etc etc and still enjoy your gaming.
Also there is a rumour around PS 5 will be backward compatible, that means it can run PS 4 games.