I guess I'll leave this thread open to see/read other users opinions about this.
Really at first glance, it doesn't seem to make sense. But the logic is quite simple.
If you ignore a board, it means you won't create topics or post there either. So in reality everything works fine.
It is true that the system could handle this list of topics differently for its OP. However, this would require deeper changes to the forum software. I believe it is not very feasible to make these changes. Maybe @PowerGlove can see if they can make any changes in this regard.