I'm responding to this way late, but I found this and had to chime in-
To address the box office thing, the biggest issue was the disappointment in the domestic market - America is not big on the Wizarding World like Europe and parts of East Asia are. I don't think this franchise is in any danger, and looking at some of these ridiculously melodramatic claims is just eye-roll worthy. Seriously, erroneously ending the film franchise with the third one because one film in a franchise with zero title/brand recognition grossed 653 million globally...this film in question being a sequel to a film with even less proof of concept that grossed 800 million worldwide, netted positive reviews, and the Wizarding World's first Oscar win, and a Bafta win to boot? Come on you guys, use your brains. Warner Bros would not terminate their most consistently acclaimed and lucrative creative universe/franchise because one of the 10 films released so far took a stumble. Be realistic here - the fact that you even entertained the idea that they would terminate the franchise at film 3 just shows that your criticisms are overwrought, baseless, arbitrary, lacking in intelligence, wildly melodramatic, and pre-determined. That's what you, for some mean-spirited reason, want to happen, not something that would remotely happen.
They made quality films - that's my problem with a lot of these pre-determined criticisms. I think you were aware there was a huge element of pre-determined hatred even before Fantastic Beasts 1 came out? I don't buy the Crimes of Grindelwald negativity at all - a number of the Potter films were poorly constructed, poorly edited, horribly paced, shoddily designed, badly acted, and poorly directed in ways Crimes of Grindelwald was definitely not. Crimes of Grindelwald represented a high water mark for creativity in this franchise. I loved the film because it seemed much more creative and much more candid and fluid in the way it represented it's magic than any of the Potter films did. The world-building was spectacular beyond anything in Potter, the themes were specific and strong, and the design was objectively amazing.
Crimes of Grindelwald (and the inexplicably better reviewed Fantastic Beast and Where to Find Them) both falter from trying to fit too much into some of the shortest films in the entire franchise. There is no reason why a story that takes place across continents, about a global war, with an ensemble cast of characters, should have only 5 films, 2 of which are limited to 2 hrs and 13 min - versus the POV story about one kid set in one setting for the vast majority of an 8 film story, a number of those films totaling just over 2 hrs 30 min long. The Fantastic Beast films are otherwise excellently made, and much more cinematic and inspiring and interesting than the Potter films, imo - but they're too short for the story they're trying to tell.
The negative reviews are really just pure psychological shaping. You had hatred of Rowling and Depp going into the film that engendered harsh, pre-determined negativity, and the usual cohort of Potter contrarians who's modus operandi is condescension and patronization towards the brand - the "Harry Potter is for kids" crowd, who always pearl clutch in their reviews about "how dark!" each new installment is. These people are often determined to view the franchise through a diminutive, rose-tinted lens in an effort to prevent the series from receiving any ounce of credit for it's maturity. This is a problem, because what you end up having is a demographic of people who simply refuse to take the story as seriously as it requires you to take it, and who are approaching the film with a lack of investment and a childish regard that is insufficient to enable anyone to properly follow and understand the story at hand. These same grown adults take Star Wars and Marvel films deadly serious, but refuse to do the same for Potter, which has always been much more adult in theme.
The-"The film sucks! The title says Fantastic Beasts and it's not about Fantastic Beasts"-crowd are sort of what I'm talking about. To be so obtuse that you 1) can't understand metaphor and 2) take everything literally enough that you develop expectations that the film will be something that it clearly isn't, and isn't trying to market itself as, is honestly staggering. This isn't Pokemon, Bob. Come on.
It was agenda-driven criticism that's to blame for the negative reviews. I haven't heard a single emphatically negative review outside of the internet. Everyone I dragged along to the film liked it, my dad and friend giving emphatically positive reviews, and my brother saying it wasn't the greatest, but was definitely a decent, intriguing and well-designed film otherwise.