@LadyAofPineapplethere are a few elements to the archaeology aspect of the pack. There's the excavation and then the analysis of Omiscan Artifacts. It's physical and mental I suppose, it definitely drains their fun but I hope they don't get burnout too, I've got 2 Jungle Adventure explorers to add soon.
Edit: it does indeed affect the Jungle Adventure pack. It doesn't seem to happen when excavating dig sites but it does affect authentication of Artifacts. So all I'm doing to limit it is to just do the dirt clump stage then stop the process halfway once the artifact is out of the dirt clump and then send the item off for analysis.
Unfortunately it means my Sim can't work from home analysing artifacts through the mail like she used to and she also can't use this method for skill gain either. How disappointing. It's really spoiling the game now. We need a way to mitigate the effects or we're losing important parts of the game. There is no upside to this feature at all.