Were you able to learn from all ranks; or from just those who outranked you?

I most certainly learned, and continue to learn, from leaders, peers, and subordinates. On a SF team we are divided by specialty and each specialty is that subject matter expert on a team. Each specialty must maintain proficiency on the newest equipment and TTPs in his field, team training is continuous.

Those who have learned only from those who outrank them are not doing their jobs. It is impossible not to learn from those junior to us if we are paying them the attention required of us as leaders. Even without soliciting feedback we should pick up on some things to improve just based on their reactions to our decisions.

Not always, but often, feedback from the most junior personnel will be marred with less politics and much more straight forward.