In real life, people don’t talk the way they do in movies or television or (especially) books. Real locations aren’t styled, lit, or shot the way they are on screen. The basic conceits of point of view in literature actually make no sense and are in no way “realistic.” Realism isn’t verisimilitude. It’s a set of stylistic conventions that evolve over time, are socially agreed upon, and are hotly contested. The presence of these conventions is not a sign of quality. Departure from them is not a sign of quality’s absence.How much research should you do for your novel? Only as much as will serve the story. I don't have a lot of patience for mystery novels that delve into minute detail about the science of forensics or science fiction stories that explain quantum mechanics at great length if it is not connected to the story. If you're going to explain the latest police equipment that can detect DNA strands in month old chewing gum, then the cops had better use that equipment to catch the crook. If you wish to spend pages explaining how your science fiction hero's laser rifle works then the mechanics of the laser rifle had better be a plot point in the story - repairing it or scrounging up ammo or whatever. If I just wanted an infodump of technical details, then I'd buy a nonfiction textbook.
The Realism Canard is the most depressing trend in criticism I have ever encountered. I would rather read thousands of posts of dismissive snark about my favorite books than read one more blog post about something that happened in a work of fiction wasn’t realistic or factually accurate to our world as we know it. … [W]e’re talking here not only about the complete misreading of what something is (fiction vs. nonfiction), but the holding of something to a standard it isn’t trying to attain and often isn’t interested in (absolute verisimilitude). We’re talking about the reduction of truth to accuracy.
People buy fiction because they want a good story. If the story kicks ass and the characters are awesome, then it's unlikely that they'll whine about niggling details. And if they do? IT'S FICTION.