He played center in a playoff game Embiid missed in 2021 and scored 19, 11, and 10. He's played 4 playoff games in his career without Embiid and averaged 23 PPG and 11 APG. Granted, he didn't play center in all four of those games. The 76ers never had adequate spacing because Embiid and Ben (and even Tobias) like to operate on the same parts of the floor.. Embiid was forced to play on the perimeter more to the detriment of his game while Ben would hang in the dunkers spot. The fit was just clunky.
The Nets are almost a perfect fit for Ben. The shooting from KD, Kyrie, Seth, Harris, Mills, Warren allows him to play in a modified Draymond role with more juice as a penetrator and paint scorer. He's still gonna have his struggles in the postseason and teams won't guard him on the perimeter but that environment is so much better for him than Philly's. The problem is he's going to have to be play most of his minutes at center because the spacing is too poor with him and another traditional center.