Gary, I don't think your writing sucks at all. I enjoyed this article very much. It was candid, clear, and observant.

Yes, it is depressing to see that an article is being read by a lot of people, only to find that they are mostly external readers. I've also found that I sometimes get external readers even when I don't advertise an article outside of Medium. Sometimes they appear on Google search results, I think.

The purpose of sharing stories with external readers is the hope of earning referrals from them--as in, converting an external reader into a Medium member when they join Medium through your link. So yes, you do still want to advertise to external readers, if you can have a hope of getting fresh external readers and not just your Aunt Sally all the time.