Walking a mile in another's shoes: blisters or insight?

     I am, perhaps, cursed in my use of language. I am unable to not hear language BOTH literally and figuratively. While this helps in inflicting punishing humor, sometimes it also forces my mind to look at issues from multiple points of view. This is almost always helpful as it is difficult to find many issues that have a single "correct" point of view.
     Of late, there have been various articles chastising people about attempting to write fiction, or non-fiction, from others' points of view. In some ways, this is certainly valid. I, as a pale-skinned male, will never have the insight, history, and experience of someone who has grown up with non-pale skin. I will never have the insight, history, and experience of someone who grew up as a woman. And -- they will never have the insight, history, and experience of growing up as a pale-skinned male. It works in all directions.
     It goes much further, however. I am a short, pale-skinned, early balding, white-haired, bearded, 60-something male, multilingual, U.S.-born but of mostly direct European with a trace of Melanesian ancestry, .............
     In other words, I -- as is true of every person of the approximately 7.6 billion people on the planet -- am unique. No one else has the complete combination of my genetic history, environmental history, and life experiences. I have considerable doubts that it would be possible to raise two clones such that they end up exactly the same at any point in time (the older the more divergent).
     Was Jane Austen able to truly write about Willoughby? Was Isaac Asimov truly able to write about the Mule? Did Ursula K. Le Guin have a similar history to that of Argaven Harge to be able to write about the character? Could Harriet Beecher Stowe directly relate to either Uncle Tom or Simon Legree?
     Back to the title of this blog. The saying goes that one cannot understand another until you have "walked a mile in their shoes". When I hear someone say this, I cannot do anything other than wince. After shoes are worn by someone for a while, they change shape -- they "mold" themselves to the wearer's feet. Some shoes, such as hiking boots, are specifically designed to do this. So, by wearing someone else's shoes, you not only are "stepping into their paces" but are trying to get your feet to react the same as the other person's feet. Bumps, muscles, and bones fail to match up. It is painful, as well as educational, to "walk in someone else's shoes".
     What should it be? Since every one of us is unique, should we be limited to only writing about ourselves? Or is the painful experience of trying to put ourselves into another's shoes a worthwhile stretch of imagination and understanding? Perhaps what is needed is the caution and respect to not try to pretend we know more about the other than we possibly can?
     Although we are all unique, I probably have sufficient commonality with another computer programmer to be able to write somewhat about what that experience is like within another character. I am not a life-long farmer, but I have driven tractors and pulled spring-tooth and fed cattle in the winter. Can I use those experiences within another character? My father was a machinist and a mechanic -- can I use those experiences even though they weren't mine? Can I possibly write about a non-pale skinned programmer even though I only have overlap in experience in the computer science and programming aspects?
     Personally, I hope so. I would hate to lose all of the literature of the world and to have only facts listed, without people, in non-fiction books. The lead character of my first middle-school book is a young woman. Is that bad? I don't think so.