True, but IMDb's user scores are often radically different than other user review sites. For instance their The Last Jedi user reviews were significantly higher than Rotten Tomatoes and Metacritic, I think it was something like 7.1/10 on IMDb vs 40% positive and 2.5/5 (or 5/10) on Rotten Tomatoes last time I looked. Another for instance would be Star Trek Picard, 7.5/10 on IMDb vs a 47% overall, 37% season 2 on Rotten Tomatoes. I personally suspect there is some kind of left/right political divide between the audiences who use IMDb vs the other user review sites, with IMDb's userbase trending further to the left, as I have noticed that the left wing fans tend to like the Star Wars sequels and the newest Star Trek fans while the right wing fans don't. That could also explain why IMDb's user reviews are lower than the other user review sites, with the left targeting it with lower scores due to JK Rowling's stand against trans people invading women's spaces.
Personally I saw Fantastic Beasts 3 last night and enjoyed it, it was actually my 3rd favorite movie I have seen for the first time this year so far (the other 2 were Guardians of the Galaxy 1 and 2 which I watched for the first time on my full MCU chronological order rewatch). I liked it better than other MCU movies that I saw for the first time this year like Black Panther, Thor 2, Captain America 2, Ant-Man, and Black Widow. I agree that FB 3 is better than 2, but I personally thought it was about on par with the first.
I quite liked the new character, Lally (in fact she is my new 2nd favorite character of the series after Jakob), the action scenes were the best out of the 3 movies, and I enjoyed the overall storyline in spite of the predictable twist. On the downside, I wasn't overly fond of the amount of focus on the Dumbledore-Grindelwald gay relationship, nor did I like that Tina's role was limited to a cameo appearance.
The movie wasn't really targeted on IMDB though which is easy to tell when looking at the score breakdown. 5% giving it 1 stars isn't really that high and compared to the prequel the 10 stars ratings grew more than the 1 stars ratings.
The median is 7 (and it's not even close) and the second highest score is 6 so a total score in the range of 6.5-7 is totally plausible.
My problems with the movie:
The movie title is highly misleading.
a) it's barely about fantastic beasts this time around. If it wasn't for the Qilin (which only appears here and there) it wouldn't even have more beasts than any regular Harry Potter movie. Even Newt's beast sidekicks (Niffler and stick guy) barely do anything. Not to mention literally everything else that is in his suitcase. In some scenes they even added some beasts in the background just to remind the people that they are watching a movie about mystical animals.
b) what exactly is Dumbledore's secret? That Credence is a Dumbledore? Uhm we already know that from the prequel. That Grindelwald is Dumbledore's former lover? Okay but that's not only not really that important but we already knew that they used to be best buddies.
Credence, who is basically the main plot device in the second movie got downgraded so much in this movie that he became completely irrelevant. He's no threat at all. Then he got a change of heart out of nowhere. Dumbledore only told him that Grindelwald lied to him and the only truth is that he is a Dumbledore. Am I supposed to believe that these words (without any proof I might add) are enough to not only calm his anger but also to tip him over the edge in becoming a good guy? I guess they just want to phase out Ezra Miller as fast as possible.
Queenie, who joined Grindelwald for no reason at all in the second movie does another sudden 180 and immediately marries Jacob. Terrible character development.
Newt got downgraded a lot too. He used to be THE main character of the series but now he's barely more important than any of the other characters. He's also completely irrelevant for the ending of the movie. His assistant did more for the story than he did. Newt was only important in the opening scene where he got the Qilin. After that he did nothing of significance (saving his brother didn't matter either for the story).
What's with the International Confederation of Wizards stuff that had no significance in any other Fantastic Beasts or Harry Potter movie/book? Now it's suddenly a big thing.
What's with the part where the "Supreme Mugwump" Vogel said that it's well known that a Qilin can't be influenced by magic yet Grindelwald can just create a zombie Qilin that does what he wants and other than that acts just like a regular Qilin...