I recently stumbled on an old but interesting article on the Grammarly Blog about the Oxford comma and why its use (or non-use) gets folks fired up. For much of my life I was blissfully unaware there was a debate over this tiny bit of punctuation. My elementary school taught the gospel of the Oxford comma, so I’ve used it religiously even since. It wasn’t until recent years while editing reports at my day job that I noticed many others don’t use it.
Use of the Oxford comma is stylistic. Some style guides call for its use while others don’t. I personally don't see what the controversy is. The Oxford comma makes things clear and it also establishes a visual pattern as part of that clarity.
Like style in clothing, I recognize why others have a personal style that differs from mine…but I know my style is right for me. So I’m a black leather jacket, Oxford comma kind of guy, I guess. No apologies.
https://www.grammarly.com/blog/what-is-the-oxford-comma-and-why-do-people-care-so-much-about-it/