Having seen the movie, I did take issue with how the movie frames Arthur as a sympathetic character and that did make me pause a bit considering our current cultural climate.
Even in a vacuum though, I still would call Joker a very middling movie as there's much better movies that explore the ideas in the film better.
I'm also of the opinion that the film does not cater to incels as there's no real ideology that Arthur follows, so that angle is completely manufactured by journalists who don't know what the word incel actually means. Arthur is just a sad, lonely sack of shit in the film. He has no underlying philosophy that pushes him to his ultimate demise as Joker. He's just an abused, mentally ill person that the film implies has no choice in what he does because he goes off his meds, (a very gross depiction of those with mental illnesses I might add) has a troubled childhood and becomes psychopathic as a result of those things. He's not at all motivated to violence because he can't get laid. He has absolutely no interest in sex as far as I could tell. He wants the world to quit treating him like shit and is desperate for a friendly face.
I think the film would have been infinitely better if it had stepped away from mental illness and troubled childhood completely. Those are such well worn tropes in Hollywood, I'm completely over directors and screenwriters who have no clue what they're doing wield them like blunt hammers to blame instead of letting their characters shoulder the weight of their actions fully. It would have been better if Arthur, sound of mind, delved into his violent end as a result of his perceived forced loneliness since he takes no steps to reach out and find people who might be friendly to him.
It is not society's fault that Arthur became Joker. It's Arthur's fault, but the movie shields him by blanketing mental illness and abuse over him. And there's not a single character Arthur interacts with meaningfully that isn't a massive dick to him. It's extremely easy to walk away from the movie with a sense of sympathy and pity for him as if he deserves any.
I do think the controversy is overblown, the film is not good enough to warrant so much hand wringing and discussion. It's barely surface deep, any movement it inspires, if any, will be shallow as hell and will die out by next year. But I also understand where the concern comes from considering America's current climate. It's ultimately nothing and probably hurts more than helps anything, but this is the hell timeline we're living in currently where everything feels like raw nerve exposure.