In an interview with Famitsu (translated by Siliconera), Ryan confirmed that the team focused their efforts on implementing backwards compatibility with games made for the PlayStation 4, while also focusing their efforts towards other areas. As a result, they were unable to implement backwards compatibility from games released on the PS1, PS2, or PS3.
“We keep in mind the engineering specialized for the PS5, as we produced the device. In the midst of that, the PS4 already has 100 million players; we thought they ought to want to play PS4 titles on the PS5 as well indeed, so we included compatibility with the PS4,” said Ryan.
“While implementing that, we also focused our efforts on taking in the high-speed SSD and the new controller DualSense at the same time. So, unfortunately, we couldn’t reach the implementation of such compatibilities.”
In a separate interview with The Washington Post, Ryan revealed that “99%” of Playstation 4 titles would be backwards compatible on the Playstation 5. During the Playstation 5 Showcase, Sony revealed the Playstation Plus Collection – multiple Playstation 4 titles that PS+ subscribers would have immediate access to on the day the PlayStation 5 launches.