Everything about Leto just rubs me the wrong way. I don't have any concrete singular incident to base it on, but just bits and pieces I know about him as a person makes me dislike him. How much I can "separate the actor from the person" is a spectrum. Leto *should* fall closer to the "I shouldn't let it color my opinion of his performances" end, but I just can't shake this dislike I have for him.
So taking that baggage aside... yeah every piece of him I've seen in Suicide Squad media has made me cringe cringe cringe. It was my kneejerk reaction at first, but it has held all the way through to now. I agree with anyone evoking Hot Topic and r/I'm14andthisisdeep. He seems to be playing up an affectation of a teenager's understanding of a psychopath than really embodying a character, no matter how "method" he's getting. In fact, all those stunts seem like an attempt to fool people into thinking he has truly become the Joker, when it looks to me like one big cheap imitation of some half-thought-out superficial notion of what The Joker is.
I'm ready to admit that maybe the movie just isn't for me. I don't like the aesthetic of the film or the the director, David Ayer. I didn't care for the Bohemian Rhapsody trailer. If I were a professional film critic, I'd pass on reviewing this movie because of my preconceived biases against nearly everything about it. Reviews and opinions are subjective, but I'm almost certain to dislike this movie.
Still, by now I've strongly internalized the notion to not judge a film on promotional materials. 99% of the time I go into a blank slate right before a movie starts, which often leads to changing my mind. Maybe that could happen here.