Let us free to savescum and give us an ironman for those against it.
I thought of an alternative solution that may balance the Save Scumming to reroll an encounter and Saving to shield progress:
Aside from the Autosaves the game applies, tie Progress saves to Short Rests (we have 2 of them) and perhaps the Camp and Waypoints.
You get 2 "free" saves out in the world but need to either return to camp or a Waypoint location for additional saves. You can still do it 100 times if you want
but you have to leave the region ... in essence, pulling you out of the action. It becomes a choice; "do I use a short rest to save? Leave and come back? Or, roll the dice and take what comes?"