But „doesn’t remember anything“ could exactly be the point for gojo to think about a back up scenario. Not knowing what happens with a natural Desaster like Sukuna is a bit risky. I don’t know what exactly could be done, i just say, I can see gojo being prepared for that situation.
Basically, you need to know what you are protecting against/fighting/doing in order to give an equivalent exchange.
I'm not saying Gojo wouldn't be able to come up with smt and use it, I'm just saying Yuji doing it seems improbable for now