Yes, I do find the doomsday prophecies very tiresome. Most people can already tell that this game will be a success. The question is how big is gonna be. And it deserves criticism of course, why it needs it, that's the point of the EA. But still, acting like BG3 won't be a successful entry for both Larian and DnD games, is just not realistic.
Don't know what "most people" mean, but the state of the game for 4 years of development definitely isn't good. It still only has 1 act, lacks half the classes, a proper reaction system, day/night cycles and still doesn't play like 5e D&D. On GoG it has a score of 3.8/5, or 7.6 which in my view is a disaster for a game with this legacy. And most of the criticism in the reviews is the gameplay and comparisons do DOS, which the developers still insist in not addressing.
We have no idea how much of the game is done. Early Access will only contain the First Act, as previously stated. Day/night cycle was never promised, you are just expecting it for some reason (as if it were some crucially important element and not a vanity item). The game is missing Barbarian, Bard, Monk and Paladin. How is that half of the classes? For me personally, this game feels to closest ever to playing DnD on my pc, so that's your personal feeling probably and not an objective truth about the game. On that tired troll argument that "this is just DO in BG skin", with every update BG3 becomes more and more uniquely new and fresh as a title. If you don't want to see that, that's your choice.
The day/night cycle and weather system were in Baldur's Gate I&II if I remember correctly, and not having those in Baldur's Gate III would be a definite loss.
The importance of things that only have an effect on what is seen shouldn't be downplayed.
Day, night, rain, snow, etc. all affect atmosphere, and in some games, they also affect gameplay.
Since Baldur's Gate III has environmental effects, I think that it would make sense for those to affect gameplay somewhat.
As for classes, there are 7/12, which is only one class beyond half.
However, I doubt that they'll wait until the game is out of Early Access to release the other classes.
About Baldur's Gate III being Divinity: Original Sin with a Baldur's Gate theme, trolls might also be saying that, but it doesn't seem incorrect.
Equipment names? Baldur's Gate.
Spells? Baldur's Gate.
Races? Baldur's Gate.
Combat system? Original Sin with Dungeons & Dragons elements.
User interface? Original Sin.
Party size? Original Sin.
Party management system? Original Sin.
Lack of a weather system? Original Sin.
Lack of a day/night cycle? Original Sin.
A lot of interactive objects? Original Sin.
A lot of environmental effects? Original Sin.
Story structure? Original Sin.
Party member names? Original Sin.
Party member personalities? Original Sin.
Some of the elements from the Original Sin games are definitely an improvement over the original Baldur's Gate games, but overall, Baldur's Gate III is far more like an improved Original Sin with elements from Dungeons & Dragons than an improved Baldur's Gate.