Of course porn isn't a real substitute for sexual education or exploring with another real human. But you appear to claim that it's practically useless because it doesn't provide everything. That's a false dichotomy: porn can be helpful in some ways, as the GP mentioned.
> Porn is to sex education as war movies are to combat training.
Right, but the options aren't only "war movie" or "real combat training". For some folks the options are porn or a vacuum of information. You can find plenty of regular, non-porn-actor folks having regular sex online. Are you saying this can't be valuable, especially when someone knows next to nothing about sex?
To use your metaphor: as a young and untrained person, would you rather be dropped in the middle of a battlefield with no explanation, or would you rather have watched some videos of real combat first?