"Like a fish out of water," used to describe someone or something that is completely out of its element, milieu, or indigenous turf, is actually a bit of an odd simile, as well as being cliche. Being cliche, it doesn't get much analysis even if it may still get some use.
When I go fly-fishing now, it's strictly catch-and-release, with barb-less hooks and a careful return of the unharmed trout to water. However, I grew up catching and keeping fish, chiefly because my family ate them regularly. Native rainbow, with the occasional German brown or Eastern brook trot, were part of our diet. Among my earliest memories is of my father going fly-fishing "down to the river" after work, returning after dusk with a creel full of trout, and dumping them in the porcelain kitchen sink. The smell of the slimy trout--with bits of fern stuck to their slimy sides--was overwhelming but appealing. As a child, I viewed the event simply as part of life, the fascinating thing unfolding before me. Now I'm more likely to think that he was a) getting out of the house & away from the family to clear his head and de-compress, and b) supplementing the grocery budget.
Later, when I started catching fish, I decided early on to knock out a caught fish--euthanasia. I'd read somewhere that Native Americans had done that (I have no idea if that's true.). --For a fish out of water is a fish experiencing a kind of drowning, slowly.
So the simile doesn't really work because it's supposed to suggest discomfort--maybe extreme discomfort, culture shock, to dredge up, so to speak, Toffler's term--but not reverse-drowning or death. It certainly does suggest that a person is out of his or her element--but it goes too far.
Assuming "fish out of water" is more poetic than literal, I think I've been a fish out of water a lot in my life. As I've moved from place to place, the places have seemed quite different from the earlier places. Remote town to suburban high school; suburban high school to community college; cc to large state university (full of pre-meds and pre-vets, while I studied English); undergraduate life to the labyrinth that is graduate school; and on to a liberal arts college, a kind of college with I was completely unfamiliar. At the same time, let's not lose sight of the fact that I'm male and white, and even though I certainly had to work on the way from there to here, I didn't have to incur the debt that most college graduates incur now.
At any rate, I think I've been more like a fish from a high-country creek that ends up in ever larger rivers--murkier waters, more fish, more kinds of fish, more complicated rules, a deceptively deadly current. Like most people, I've not been a fish out of water (thank God), but a fish in different waters. The main thing is to keep facing into the direction from which the water is flowing, look for food and other sustenance, be cordial to other fish who may swim one's way, and hope that if God or fate is fishing that day, the fisherperson is practicing catch-and-release.