Board Thread:Questions and Answers/@comment-26572409-20150704135123/@comment-25192437-20180209090743

Ichigo's high level of spiritual awareness was due to his parentage - he had a Captain Class Soul Reaper-in-human-form father and a pure-blooded Quincy mother.

Uryuu kept to himself prior to challenging Ichigo to a duel, and if Aizen's hypothesis is correct his friends wouldn't have developed powers without Rukia being present - which was after Ichigo's Soul Reaper powers were activated.