This. And this is where actual high end shocks that are able to be tuned come into play. Bolt ons are going to compliment the suspension mods as well as something you can tune.It does. The same reason it increases body roll is the same reason the suspension is more compliant. Less bind in the arms and track bar. This is an argument for the 3 link rear. Otherwise, all you can do is tune out the added roll with shocks and sway bars.
This isn't specifically because of the mid arm configuration. It is a phenomena of a 3 link or 4 link.