PS4 Pro cannot play UHD blu-ray discs because it is "primarily for gaming", but the Xbox One X can, Just so Sony can sell you a $300 UHD blu-ray player. : r/assholedesign
Genuine Sony PS4 Blu-ray DVD Drive Replacement with BDP-020 BDP-025 Circuit Board KES-490A KEM-490AAA Laser for CUH-1001A CUH-1115A CUH-10XXA CUH-11XXA Sony PlayStation 4 models with Opening T8 Tool : Electronics
PS4でDVD・ブルーレイを再生する方法・再生できない対策
What Happens When you put a 4K Ultra HD Blu-ray disc into a PlayStation 4 Slim ( PS4 Slim ) - YouTube