It's very rare to see a movie rake in hundreds of millions at the box office on its opening weekend these days. There are outliers, but generally speaking the days of mega opening weekends are a thing of the pre-Covid era. Because of this, we've seen movies struggling to generate enormous opening weekends and while Mission: Impossible - Dead Reckoning Part One didn't have a bad debut, it hasn't had the biggest debut in the series, at least judging by Box Office Mojo figures.
The film has netted $235 million at the global box office, which is getting close to already seeing it recoup its production cost, which was reported to be $290 million.
As for why the movie is down on former instalments, the domestic earnings are down by around 10% when compared to Mission: Impossible - Fallout, and the international earnings are down by fair percentage as well, but this seems to be attributed to the decrease in the Chinese box office ever since the pandemic, as Dead Reckoning Part One is actually above Fallout's earnings internationally and excluding China (China's earnings are 66% below what Fallout raked in).
If you haven't managed to catch Tom Cruise's latest outing yet, be sure to read our review of the movie here.