Just wanted to respond to this because I skipped it in my previous reply (because I didn’t disagree with it). I’ve been thinking about opposed rolls for my game, and I think I see their logic. I’m not sure it’s D&D influence. If you think about how the game will flow at the table, doing it the way I suggested (attacker is rolling to overcome a defense/resistance), it’s going to flow awkwardly once you get outside of the martial combat case. Imagine trying to resolve an area effect (e.g., like fireball) where the defenders had to roll first.Since the designers originally started with D&D, I don't think it was so much the effect of different games and their resolution systems, but that when they went with their 2d6 system, they had to decide what to do with ties, and since resisting magic fell under the saving throw system in D&D, they went with that as the base. The swerve, as it were, was that they then applied that to the to-hit roll, as well.
It also seems like Sword World isn’t unique in this regard. Konosuba TRPG and Shadowrun also work that way. When D&D does opposed rolls, it’s the one doing its own thing (3.5e has you compare modifiers while 5e suggests there is no progress by either side towards the goal). I guess that was my experience speaking.