Yep, it is confusing as to why Medium chooses some writers over others. There are many good writers here with interesting things to say. But the "preferred writers" are able to get new followers because they are put on feeds for no other reason than they are famous--and that perpetuates the myth that readers really want to read their work.
With one exception, I try not to click on the famous Medium writers. And there is another writer who I will click and respond about once a month, just because I get a little traction dogging under his popularity.