Each of us is sensitized to different things. A doctor friend watched less than 60 seconds of the original "E.R." TV show because in that minute he saw someone use an IV upside down. That made the entire show untrustworthy.
It rarely takes a lot of effort to get it right. Why not do so?
Because, contrary to your claim, it takes a lot of effort to get it right, since there are a near-infinite number of ways every individual element of description or presentation can be wrong. And it's often a high cost:benefit ratio, because most errors will only be noticed by a small share of the target audience and will only break suspension of disbelief in an even smaller share (conversely, getting it right will often strike non-experts wrong and break suspension of disbelief; verisimilitude in fiction is not actually about matching reality, but audience expectations.)
So, except on the things about which your target audience is particularly knowledgeable and concerned, accuracy may not be worth the effort put into it.