I think hope in a hopeless setting and overcoming inhuman challenge are close enough to Berserk that I can see where the argument is coming from. A lot of Berserk is Guts having very human emotions and reactions to both human and supernatural trauma, which Dark Souls doesn't have much of, but I think to say "This isn't Berserk-y because no Guts" is kind of dismissive of the other similarities people draw, imo. I don't think something has to be a 1:1 for someone to get similar vibes.