I strongly doubt that. A roller shutter is ventilated with outside air behind it, how is that supposed to insulate? Heat protection through shading: sure, but it doesn't insulate.
We have experienced that rooms cooled down faster when the roller shutters were up. When the roller shutters were down, the rooms stayed warm longer. No joke! We tested this once. However, in our old building, with plastic roller shutters and double glazing in aluminum from 1975.
Whether this still applies to the shutters installed today, we cannot say yet. We are doing the interior fittings but are still at the beginning. The principle of roller shutters has changed a lot.