Maybe a paper does stand on its own, with the large list of citations at the end. But, maybe some of those citations are journals that your institution doesn't subscribe to, or are historical and in another language, or et cetera.

There is a page limit to publications in high impact journals, and generally it's not great practice to utilize the limited space on the details of hurdles overcome.

I would argue that some of the most important papers in science don't really stand on their own... they need context and expertise that the paper can't and shouldn't cover.