Poor franchise of J. R. Rowling did not deserve this fate. The third movie of the series was cinematically better than the third, but... The whole meaning of the story has disappeared because of disappearance of Johnny Depp and now-you-see-it-now-you-don't homosexuality of Dumbledore.
There was a motivation difference between chief antagonists Voldemort and Grindelwald, which the producers erased between the second and the third series, not unlikely to Benioff who forgot the character differences between King Jeoffrey and Ramsey Bolton so by the end they acquired virtually identical personalities (Game of Thrones). Voldemort's agenda had obvious parallels with Nazism: striving for a society of the elect based on racial hierarchy and headed by a leader of questionable racial purity. Grindelwald of the first two series had a completely different motivation, even if it was not sufficiently enunciated, based on the revolutionary movements of the early twentieth century. Namely, the old world ("muggles") let the world into a catastrophe of the Great War and promises even worse disasters in the future (it did). It persecuted sorcerers and witches. Now it is the time for a new world, safer for everyone and led by the magi for the benefit of all. The strength of the premise and its connection with the previous "Harry Potter" franchise was in the message that the desire to make people happy by force can be as destructive as the desire to oppress everyone by force.