Bertholdt doesn't strike me as a mirror to Mikasa, but still he subscribes to a part of her ideology in his final moments.. because the world is just that cruel
maybe the whole thing of a cruel but beautiful world is an underlying theme throughout aot, but I always saw it as a Mikasa thing.. Either way my thoughts drifted back to Annie as it does and I feel like the use of this quote shows the contrasts between beruani and mikannie really well!
In my mind, beruani works in a pretty regressive way where because they were brought up on violence, they never grew out of it especially if their only support on the island were each other in secrecy... And this violence of course would fester more (especially in Annie and her explosive issues) without an outlet and they'd accept it.. because the world is just that cruel
but with mikannie (as an endgame relationship or even in general) Mikasa understands that the world is cruel just as much as Annie does, but she still finds beauty in it through the people around her.. I think this pairs well with the nihilism Annie was brought up with where nothing mattered, not even her and also the fact that she looks up to people that could "change the world".. mikannie to me is Mikasa fundamentally changing how annie views the world and shows annie that even though they've been through so much violence, there's still "good"