Worse, the level of technical description in sci-fi, even in 'hard' sci-fi, is terribly low. You really can't say a submarine 'powered by the sun' is the same a

Worse, the level of technical description in sci-fi, even in 'hard' sci-fi, is terribly low. You really can't say a submarine 'powered by the sun' is the same as predicting electric subs and neither do you get credit for such things unless you really delve into the justifications for such a 'prediction' and explain a fair degree on how it would all work. Or that the communicators in star trek have anything to do with smartphones and other low-effort comparisons. Double worse, ignoring the cherry-picking sci-fi tends to do a very poor job predicting anything. Its almost as if sci-fi is written to be dramatic and follow the rules of storytelling instead of some weird futurist exercise. I doubt Philip K Dick gave two shits about how realistic or futuristic his settings were. He was too focused on the characters and the story.