if you feel you are beeing incentivized to savescum if the game features the option to do so then maybe you should limit yourself to one save.
Seriously thats on you.
Oh this is actually very easy to implement, a lot of games offer an ironman mode as such that disables hsving any more than one save file.
Usually ironman challenges become a thing after mastering everything over hundreds of playthroughs in such a game, as I have done in BG2 a few times.
Things like having a full perfect custom party and knowing to have a full caster shutdown sorcerer and archer tag team trivialised BG2 without such challenges. Realizing as well just how powerfully broken the polymorph self spell was, and them making a fully buffed sword spider to just cleave through every encounter, while it was also immune to webs spammed by another caster ....
Good grief that fighter / mage I once made running around as nothing but a sword spider. Bite poison dead, bite poison dead, bite poison dead, bite poison dead.