This line of Sans' at the end of UT never hit harder than it has after DR started raising the chances of it actually being a far-removed prequel to Undertale.

Sans is obviously an asshole in DR, and yes he retains some of that energy in UT, but he's a tempered asshole with a serious side who, in spite of being so jaded, clearly has some kind of commitment or duty to something that we don't fully know about. So, what kind of fucking horrible shit does an ass like him have to go through in order to be transformed from one into the other? What apocalyptic torture is going to happen to this man at the end of Deltarune that, in Undertale, makes him defeatedly say this kind of shit when his soul is stripped bare to its most truthful, raw layer?

Just kinda wild to think about.