This is not a fun kid or even family friendly franchise. It's heavy and it's dark. Dark sci-fi has never been a hugely popular genre in film.
The previous film opened to $41m. Yes it was Covid and HBO Max but even then it didn't hugely break out on streaming. It did well but not Batman Begins or Austin Powers home media crazy. But it's going to open at least 70% higher. How is that disappointing? How could one expect it to open 150% higher to a $100m plus?