Well, i think thats a fair point...
However my opinion is that the ending left me wanting more...i understand its an 'origin' movie but id like to see it as a trilogy myself the same as the 3 films with Bale as Batman.
As its just a standalone id be surprised it there werent a couple of spin off films e.g Batman + Joker with Leto as the joker...
Here’s what I’ve read off Wiki anyway:
“In contrast to modern comic book films, Jokeris intended to be a standalone film with no planned sequels.
[76] While Phillips said in August 2019 that he would be interested in making a sequel, depending on the film's performance and if Phoenix is interested,
[46]he later clarified that "the movie's not set up to [have] a sequel. We always pitched it as one movie, and that's it."
[146] Warner Bros. intends for Joker to launch DC Black, a line of DC Comics-based films unrelated to the DCEU with darker, more experimental material, similar to comic
imprints such as
Elseworlds.”
Personally I’d like it to be parked now; leave it as a Joker origin film and move on. However like said above I’d be more than happy for it to spawn say a stripped back Batman film that can then create sequels.
Some films to me are just ruined when they try milk them for sequels.