Of course step/comlex scores matter. It's the number one thing they use to assess applicants for invites and ranking.
But I will say, of the interviews I've been on, about 50% I've had PD and faculty literally look me in the eyes and say "tell me where you did your IM rotations third and fourth year" and wrote everything I said which included "I specifically had to go out of my way to rotate at an academic medical center with residents".
So there absolutely needs to be a push for higher quality, more consistent rotations which will never happen given the speed of DO schools opening and the large class sizes in some really really small cities.