People will save scum no matter what. I'm a chronic savescummer because as others have said, sometimes I want a specific outcome that I failed to properly put into motion. This includes choice games like Heavy Rain and games with more combat where I meticulously snipe every enemy I encounter, reloading if I get caught before I'm done. It does depend on the game to what extent I will save scum - sometimes I am literally fighting with game mechanics, other times I just want what I want.
I do think devs should have "heatmaps" of where players savescum often. The one change Larian did so far due to a lot of savescum data is in the initial Kagha scene.
. I think this change added something to the game, especially if they elaborate on Kagha's characterization in particular. While devs certainly do not need to make any changes based on savescum data, and accept that things are working as intended, the data can let them know that there aren't enough options for particular routes that a good number of players want to take. And making changes based on that, with respect to maintaining their artistic vision, can make the game better and reveal much of the game as properly intended.