No, he said that the souls that get lost and find their way to the Valley of Screams, because of the valley, the energy and memories of these lost souls are separated. Yuichi-kun was tooken out of his body and put into a parakeet's, thus him never going to the Severed World, never giving him a chance to get lost and find himself at the Valley of Screams.The movies are not canon. What is stated in the manga is canon, so the Yuichi Shibata version is correct: souls do remember their life when they enter Soul Society. However, when they are later released back into the living world (reincarnation is a part of Bleach), they do not retain their memories.