Many fiction writers create scenes that are somewhat unclear. I’ve read Hugo/Nebula winners works that do—regardless of POV—and that’s bad (unless “trippiness” is expressly the point of the scene, but I digress).
Plus, since third person omniscient point of view involves the changing of POV characters within a scene, (the consensus is) it is more difficult to do without making it confusing. This can all be stipulated.
However, just because it isn’t easy, doesn’t make it impossible or, indeed, even undesirable. There are stories best told in that fashion. And, frankly, when it is done well, it is powerful.
This is all to say: to my ears, when writers scold other writers en toto, for ever attempting to use OPOV (often deriding it as “head-hopping”), it sounds more than a little bit hysterical. Sort of like a checkers player decrying playing chess as “cheat-moving.”