I just see how many people argue their dissatisfaction with the fact that " BG3 is not like BG2 " or something similar. But it's normal that it's not exactly the same.
That is incorrect, or partially incorrect. The main criticism is that it deviates from the D&D ruleset too much, the current one, not the one from the BG times. No one is saying that it should follow AD&D ruleset from 1989. Another criticism is that up to now at least the story has nothing to do with the events of the BG games at all.