He knows what he wants to say: because you all tortured Ignatius, because he doesn't deserve this, because he's not the monster that Rita desperately wants him to be, because he still thinks that it's his fault that Ignatius is here in the first place. Thankfully, Strange keeps those reasons to himself and gives a different one instead.

"Because I've been in his situation," Strange explains, trying to keep his voice calm. "When we were in Portland, I was trapped in Nightshade's realm for about a week. The experience was...harrowing," there was so much torture, "but even just one person on my side would have made it infinitely better."