He smiles a little. Of course not. Of course telling the Determined human that they have to accept something, that things are how they are, is just going to lead to resistance. They wouldn't be Frisk if they didn't try to reject the status quo, the seemingly inevitable.

"yeah. i mean. what else can we do?"

People like Frisk, and Papyrus and Undyne as well--they can fight and fight and fight against something, throw everything they are against the walls of reality until either they break or reality does. Maybe it's a little foolish, but it's also incredibly admirable. But Sans just doesn't have that kind of energy. He tires out too quickly.

"but, you know. acceptance isn't the same as giving up. it's just. telling yourself you're gonna live with how things are. try to make individual moments a little better. i dunno. i just don't see much point in worrying about things that are inevitable. but maybe that's just me."

Sans is pretty okay with how things are now, here. Whatever happens happens. Everything is always only temporary, after all. There's a lot of freedom in just enjoying the fact that you were lucky enough to have something so fleeting and temporary. The past is the past, and other timelines are other timelines.

"i think it'll be okay, kid."