So much porn is ruined by many things - to the point that all porn basically has no arousal quality anymore

Cheesy music, sound missing, sound and video not synced properly, poor copying of video from what presumably was not digital media into digital format, etc. plus the actual theme/content being totally un-natural, or wierd camera changes when filmed by someone else, and a lot more

Nearly all porn has little to be sexual appeal now. That's probably a good thing, as it's basically a complete turn-off.