Last I heard he said he wasn't planning to make a 4th season of Bluey. But it was worded in a way that made it sound like it wasn't ruling it out completely.

One thing I admire about the show is that all the children actors' identities are a secret. No one outside of the show's team knows who voices Bluey and Bingo (other than the fact that they're the daughters of someone who works on the show), which probably affords those girls as much of a 'normal' life as possible, something that celebrity children wouldn't ever get to experience.

That also makes me wonder if the reason we're not getting more than 3 seasons is that their voices will change. But man, I really hope he puts out more stuff, whether in the Bluey universe or elsewhere.