It's why I loved Edward Norton's Incredible Hulk. It didn't bother with setting up the origin story - just a credits montage. It trusts that people already know who the big green guy is and where he came from (this also had the welcome side effect of the movie not being completely disconnected from Bana's Hulk. All you had to overlook was the different actors playing Banner.)
MCU is at least done with that shit. They've already established many of their heroes so they can do fuck all with origin stories and go straight to building up the current plot. It's not a coincidence that they're having an easier time bringing new properties to the big screen while Sony and Fox still trip over themselves trying to reboot everything.