GamesRadar+ reports that that the PS5 owners will also be able play PS4 games with those who play on the PS4. This allows for communities of gamers to not be split when some of them upgrade to the next generation console while others remain with the current.

Jim Ryan, CEO of Sony Interactive Entertainment (SIE), said this tech allows the gradual migration of gamer communities from one console generation to the next. While not explicitly said, this suggests that game saves can also be ported to the next generation as well. It’s great to see SIE paying so much attention to backwards compatibility. This will be especially great for multiplayer games launching near the end of the PS4’s life cycle. Those who play these games who also plan to upgrade to the next generation will be glad that they will still be able to play with their friends who do not plan to upgrade so soon.

Sony To Allow Multiplayer Connectivity Between PS5 And PS4 - 86