Changing POV is not unsmart; it simply requires thought, organization, and execution to be done properly (and that really is the only way to go about doing anything). Changing point of view between characters has become a fairly commonplace method of helping to move stories along and develop plot lines. But it must be done well. Skipping back and forth between characters can be an arduous process, and if done poorly, can have the reader missing parts of the story, or at worst, completely clueless as to what is going on in the story. But if done well, the different POVs can weave together a story that is much larger, much complex, and much more realistic than what one character’s point of view alone could have brought to the story.
I believe that this method of writing is completely dependent on what type of story/setting the writer is attempting to create. It is similar to how a writer decides on to use an omniscient narrator, or if they want to go with the more personal touch of a first person point of view. I think that single person POV stories tend to try to sway the reader to hold the same view point as the main character. After all, it usually works better for the story if readers agree with the main character. But having multiple characters’ viewpoints in a story can really change the whole dynamic of the story. The plot can be thickened, black and white can be distorted into grey, and readers have to learn to decide for themselves what side, if any, is right or wrong. It opens a whole new way to bring up plot lines to readers, or to drop information on them.
But I think it all depends on the writing itself, and the story that the writer is trying to create. If you, as the writer, want your audience to know the backing of the story, go with the omniscient narrator. If you want the audience to be swayed to one side, to empathize with and support your main character, single person is the way to go. But if you want readers to have to think, try and hold multiple viewpoints, changing point of view is the way to go. It sounds like I’m pushing for narratives to be done only with multiple viewpoints. Not true, I want narratives to be written as the writers want them to look. I simply want any narrative to be the best version it can be.