The intersection of 9th & Lincoln has a "no left turn" sign for traffic coming southbound out of the park (by the botanical garden). This makes no sense.
East-west traffic is already stopped so it faces no additional interruption from left turns. Traffic exiting 9th ave. northbound generally just wants to get on Lincoln east or west; besides, there's no need for speed when entering the park.
So there's no reason to forbid a left turn when exiting the park southbound at 9th ave. The current restriction just forces more congestion onto 9th ave., which is already pretty choked. Allowing a left turn onto Lincoln eastbound would make a lot more sense.