I definitely do not agree to that "I followed you, follow me back" thing. That is because following anyone is our choice and not because they followed us. You are correct about the functionality of Follow filter. That is why I said that you should follow those...

who write high quality articles that interests you and follow them.

and

Following will also filter your interests to be automatically on your feed instead of you searching through tags.

When I posted my self-introduction, I tried to be nice by following back. As I went along and saw how these people were doing such spam script of "followed you, follow me back", I unfollowed them.