It's the same reason No Way Home was a success; a somewhat long awaited comeback for revered characters. MCU has been striking out bad as of late so it definitely wasn't a driving factor.
shareJackman.
shareProbably MCU first, because they still have a large core audience. Many of them now stream the films at home, but the mitigating factors that got them to see this in a theater were no doubt that it was Marvel's first Deadpool film, they brought Jackman back as Wolverine, and that it had buzz.
After that, it was the hype around the film. More than anything in post-COVID times, a film has to have a buzz. Something has to capture the nation's attention and make it the see-it-in-a-theater movie of the year. Most of the people who used to see a movie every weekend now see a movie every year, and they choose the one that has that buzz. It was Barbie last year, it's probably Deadpool this year.
-its Deadpool 3 - DP 1/2 are the biggest X movies even bigger than DOFP. DP3 was always going to be huge..but even huger than ever bc of:
-the return of Jackman as Logan - not just a bit part or cameo but full on throughout the film, basically resurrected from the end of 'Logan' despite the opening credits lol (yeah hes a different Logan but still essentially the same one and even the same one from 'Logan' with similar situation of all the XMen dead except him)
-all the rumours of seeing previous Marvel movie actors (if you stayed spoiler free, if not youd be running to the theatre anyway hearing Snipes was back as Blade, Evans as Johnny Storm, Elektra etc and not just cameos but in expanded roles)
-its MCU (yeah this dosnt count for much now unless its an real event like this movie)