You are true that no plan is available. In my op, I should have been more specific. On his Patreon, the free membership replaces the follow option. To get to it, do the same thing you would to "follow." I've included a screenshot to demonstrate it.
You are considered a member after you have "Joined for free." I've included screenshots to demonstrate it.
The advantages of doing so are non-existent. Following has previously provided you with information on new public postings, so nothing has changed on the user end. DPC, on the other hand, has overstated membership statistics. Overall, it's a strange development that benefits no one.