Hi Carrie - I think the short answer to this is they just haven't thought about it. When one DOES think about it, it is the perfect way to both meet and endorse others. I clap my little hands off for emergent writers, and for writers who reach my soul, or any other part of me, and now and again, I highlight people's work, (because I edit here, so it's easier). But I now have a plan, and will do as you suggest.

Nobody can ever forget the wilderness of existing on Medium, where not a soul knew your name, and you wrote, and wrote, hoping to win the lottery of someone responding, (and you nearly gave up), and then you were rescued by a knight in shining armour,. Oh my goodness, that was a pun for me. He WAS a knight in shining armour, and his surname is Knight!

Which means, linking is a great thing to do. Great article.