Different encode. Some people think Warner’s is better. There are differences if you’re pixel-peeping. Someone on another site pointed to this example: https://caps-a-holic.com/c.php?a=3&x=740&y=256&d1=16962&d2=16781&s1=185843&s2=182372&l=1&i=5&go=1.
Whether you would see a difference in actual viewing is a different question.
Anyone who'd claim they could see a difference between those two images during playback is a damn liar. Even in still frames, all it looks like is the Warner disc is marginally noisier with no difference in actual picture detail.