Alright.
A: Steve being anywhere near the gigaton range is wank.
B: The Terrarian still speed blitzes, and Steve has no reliable way of keeping up with the former's mobility. All Steve has in terms of long range options is Bows, Crossbows, and Tridents, all of which are easily dodged via Hallowed Armor, Master Ninja Gear, Rod of Discord, or, just, flying indefinitely.
C: AP and Speed literally don't matter, like at all. The Terrarian has plenty of hax, can just inflict Acid Venom/Shadow Flame/Confusion, Throw a Love Potion, Petrify them via Medusa Head, dura neg via the Lighting Aura Staff, Transmutate them via Shimmer, etc