Yes. It’s a story about putting Subaru into situations where the only path forward is self improvement. Subaru can fight and struggle to stay the same but to move forward he must improve. In the Sanctuary arc Subaru repeatedly failed to solve all the problems himself. There’s a what if story where he goes through with the contract with Echidna and we’re shown what would have happened if Subaru gave into his Greed, essentially ruining his relationships with all his friends, while still “saving” them. He got everything he wanted while losing what was most important.