As long as you can avoid taking damage, which is actually quite hard in Terraria due to many factors including the very heavy momentum, you can defeat anything as long as you can deal any damage. We really should aim to avoid the game of "this weapon/item/build/whatever is actually slightly useful in this situation, NERF IT". A lot of us have played the game for hundreds or thousands of hours, read the entire wiki and figured out how to break the game. The game shouldn't be balanced around us. It can actually be quite challenging, and I definitely won't pretend that I find all of it a walk in the park despite having played for so long. Part of it is the random nature of it. Another part is how extremely visually noisy it can be. Yet another is how heavy the player's movement is, and how many attacks aren't designed with it in mind. The game actually breaks quite a few "golden rules of gameplay balance". One of them is that you can and will be attacked from off-screen. How many (hundreds) of times have you been exploring the underground jungle only to get hit by a barely visible stinger with a barely (if that) audible audio cue coming from off-screen? Every time you find a somewhat open area in the underground jungle there will be at least three hornets firing stingers at you from off-screen. That's not even factoring in the fact that you can't see into the clearing because you haven't been there and placed torches. In some cases potions can somewhat alleviate this, but you can't be expected to have those active at all times. Projectiles in general are often very hard to see. The queen bee's stingers, and summoned bees for that matter, are extremely hard to see in the middle of the action, and that's after the stingers were given a visibility increase at some point.
Another example is from when I was fighting the frost moon a few days ago. I had taken a few hits, so I decided to land and grab a pile of hearts on the ground. I landed, and immediately died to a bunch of those thorny balls that were completely camouflaged in a pile of weapons, trophies, hearts and whatnot. The thorny balls spawned by... I have played this game for well over a thousand hours, and I have no idea if it's the Santa tank or everscream that spawns them. The game is just that visually noisy. It's particularly bad during events such as the frost and pumpkin moons. You will be shot at essentially constantly by enemies off-screen, with projectiles that often pierce blocks. When the torch luck update came out, you know the main reason I disliked it? Because almost all the torches that you're supposed to use are significantly dimmer than normal torches, and give off colored light that is the same as the surrounding blocks, walls and enemies. It reduces visibility quite a bit. In fact, my main hope for Terraria 2 is that visual clarity isn't neglected. Game devs tend to lose themselves in details, particle effects, blurs, filters and so on. Don't make bosses like the slime queen, whose main methods of hurting you are a horde of slimes shooting off barely visible projectiles constantly, and bouncing projectiles that go far off screen only to come back aimed right for you just after you used your shield dash.