So... you, as in you the human player, would not sacrifice a race of beings you barely recognise as sentient, to save the human race? Ok. I'm pretty sure most would though.
If the human race in any recognizable form was thousands of years dead already? I'd accept that reality and move on with my life until I joined them.
Hell, Solas actually has some banter with Varric that's very on topic;
Solas: Once, in the Fade, I saw the memory of a man who lived alone on an island. Most of his tribe had fallen to beasts or disease. His wife had died in childbirth. He was the only one left. He could have struck out on his own to find a new land, new people. But he stayed. He spent every day catching fish in a little boat, every night drinking fermented fruit juice and watching the stars.
Varric: I can think of worse lives.
Solas: How can you be happy surrendering, knowing it will all end with you? How can you not fight?
and later;
Varric: In that story of yours—the fisherman watching the stars, dying alone—you thought he gave up right?
Solas: Yes.
Varric: But he went on living. He lost everyone, but he still got up every morning. He made a life, even if it was alone.
Varric: That's the world. Everything you build, it tears down. Everything you've got, it takes—and it's gone forever.
Varric: The only choices you get are to lie down and die or keep going. He kept going. That's as close to beating the world as anyone gets.
Solas: Well said. Perhaps I was mistaken.
It is so on topic that I'm almost inclined to think that Solas made up the story as a cipher for his own life. And yet he completely misses the point; he doesn't strike out on his own, find some new people and make a new life. He doesn't remain by himself, getting up every day in defiance of what the world has taken from him.
He's resolved to take everything the world has taken from him back, destroying everything everyone else has to rebuild something that is dead and gone. He isn't Anders, he's Quentin on a far grander scale.