Weapons in BG3 be like, "Dragon's Clasp Axe - If your target is on fire, you deal an extra 1d4 damage.
Weapons in D&D be like, "Longsword of Life Stealing - When you roll a 20 on an attack roll, that target takes an extra 3d6 necrotic damage. You gain temporary hit points equal to the extra damage dealt."

BG3 = you need to first set an enemy on fire, THEN you can acquire the benefits of the weapon.
D&D = there is a chance with each attack roll that you can acquire the benefits of the weapon.

There's a huge difference here. BG3, you have to meet the right conditions. D&D, you always have a chance to achieve success with the item. You don't have to first do this, then do that. It just either happens or it doesn't. (Some exceptions do apply, naturally.)

You say, "Well, just don't use it if it doesn't suit you." We say, "But they're ALL like that. There are very few items in this game currently that are like the Longsword of Life Stealing or other more normal D&D weapons. So, we either are forced to take extra steps to make a weapon more effective, being forced into using DOS surface mechanics and gimmicks just to take advantage of an item, or we don't use special items at all. There is no in between.

I don't mind weapons like Mourning Frost as long as there are also weapons like Sword of Wounding or Vicious Weapons, or Sun Blades, or Sunguard Shields. Weapons we don't have to do this and then that and then this and then that to use effectively.

And, I think part of the issue is that it's EA. Everything is jammed into Act 1. If these items were all spread out over the course of the entire game, people wouldn't have an issue with them as much. I honestly like most of the items in the game if they tweaked them a bit and spread them out.

Example: Paleoak Staff versus Nature's Snare. They give you both in EA. In my opinion, Nature's Snare makes Paleoak seem lame. Why? You can get Nature's Snare relatively easy, and its ability seems better than Paleoak. And yet, Paleoak is the reward for completing a Druid Quest.

Now, if they didn't let you acquire Nature's Snare in EA, and you only got Paleoak as a quest reward, then Paleoak would seem more rewarding because you did this big quest and you got a cool staff from it that isn't upstaged by an easier to get staff that is also Druid related.

OR Nature's Snare would be fine to get first if it wasn't as OP as it is compared to Paleoak. Nature's Snare is easy to get, so it should be something like a +1 Quarterstaff but only for Druids to wield, or something like that. Maybe give it the ability to cast Ensnare once per day if a target fails a Dex DC 13, or something really not that effective because it's an easy to get item. Then, when you get Paleoak, give it +1 to Attack and Damage plus the ability to walk on vines without getting entangled plus making it so that Entangle is always a prepared spell plus make it so that only a druid can use it, and NOW it becomes a much more awesome Druid weapon and a great reward for completing a fairly major questline.

Value. It's all about value. If you are constantly getting tons and tons of items with special abilities and traits, none of them feel special. They all feel mundane and lame because you are practically tripping over magic items at every turn.