Joker is doing so well at the box office, and cost so little to make, that it is currently on course to make as much profit as Infinity War.
It feels as if we are living in an age where if a superhero movie doesn't break the billion-dollar mark at the box office, it is considered a failure. Both Infinity War and Endgame managed it with ease, as did Black Panther. Even DC has been getting in on the fun with 2018's Aquaman also breaking the $1 billion boundary.
As for whether DC will add more titles to that club, that remains to be seen. What the franchise is doing with its cinematic universe going forward is a little up in the air. A new Batman has been cast and James Gunn is currently putting together what should be quite the Suicide Squad sequel.
As for the here and now, all eyes are on Joker, and what an impression it's making. DC has returned to its dark roots and it has worked like a charm. It might not make the billion-dollar mark at the box office, but that doesn't mean it won't be lauded as a success in the same way as what the MCU is doing right now. In fact, due to Joker's low budget, it is currently on track to make just as much profit as Infinity War according to Cosmic Book News.
Infinity War raked in well over a billion dollars at the box office. However, it's blockbuster budget meant the profit made clocked in significantly short of $1 billion. As for Joker, the movie cost just $50 million to make and as of right now has taken $750 million at the box office, meaning it can be considered as successful as Infinity War in a way.
Apparently, this will be the approach DC takes with its movies going forward. Keep the budget low but focus on the quality of the film. Judging by the cast for Suicide Squad 2, we're assuming that mantra will be adhered to once Gunn returns to the MCU. It's definitely the right route to take, though. DC has proved it can't do Marvel better than the MCU, but it does dark better than anyone, as it has done once again via Joker.