Rear tire lean at the top

[Vanguard]

I just finished out updating the front suspension and rear shocks on my son's 2001 3.0. The alignment specialist pointed out to me that the rear tires were leaning in. He suggested possible weak springs in the back. He thought that the bushings looked good.

The truck has about 134K on it. Are the springs sagging or is likely that it's some other part of the suspension?

Interestingly enough, we passed another e53 on the way home and the tires on it had the same lean going on.