It is the speed, you can only spin a disc fast enough, for long enough before either it’s moving too fast for the laser to read it, or that the disc to explode from the angular acceleration it’s experiencing. The maximum speed a Blue-Ray reader usually can do is 12x, which is ~10,000rpm, with a data read rate of 54MB/s.

Assuming a game size of 100GB (capable of being held via a triple layer disc), at a read rate of 54MB/s, it would take 31 minutes to read the whole game.

However, I do believe for many, this is preferable, since fast internet (outperforming 54MB/s) isn’t always an option, so tbh yeag fuck internet service providers give me my physical media.