Actually I think this is the same fallacy as one of Zeno's paradoxes, and has the same resolution. We are discovering more wrong, as you say, but the "infinity" of wrongs is in the direction of the infinitely small (or "infinitely detailed"), not the infinitely large. In other words, every time we fill in a gap in our knowledge, we create two more gaps, so to speak, but nevertheless we know more than we did before.