What I'm saying isn't that all players and media are stupid whiners, but that earily access gets bought by many who underestimate the issues and don't know that it has only limited content - as can be seen by comments asking for a polished game. Many players don't follow game news that closely, something that can be easily forgotten reading articles or watching streamers if you are into it and being in the loop yourself.
Comparing BG3 to Mount and Blade 2's steam numbers we can see pretty much the same trend. At release of the earily access you had 113k players on average, next month 30k and now its down to 9k (Steamspy has it at 5-10 millions and gameworldobserver at 2-5 millions, but I honestly don't know). Comparing it to BG3 with October 16k, November down to 4.8 and now down to 2.7 I think BG3's number seem pretty similar, just with a lower sale number to start with.
In any case I wouldn't judge the popularity of a game by its EA concurrent player numbers as many simply have no interest in play EA even if they want to buy the finished product (many journalists said that they don't want to play EA to spoil the later experience). Whether the game is living up to expections based on EA might be a more precise quesiton, but hard to say. For me personally BG3 was a disappointment many levels based on what they said they were going for and what we got so far, others will highly disagree as many are satisfied with the game. I guess we will only know how popular the game is once it really releases.