I wonder if it is the rise of critically conscious moviegoers (all my friends both real and on FB/twitter knew about BvS, Independence Day and Apocalypse's negative critical reception/WoM days before they came out) is contributing to this lackluster summer thus far. If so, guess that means the age of stupid "turn your brain off" blockbusters is nearing an end.
I doubt that. Warcraft, Xmen, ID4-2 all had fairly terrible marketing the entire way through. BvS at least looked good from the trailers and still will end up some 300mil+ thanks to it. Its definitely not the end of "turn your brain off" blockbusters when 2015 had Avengers, Jurassic World, Furious 7, Star Wars, and Spectre all doing bank. Each full of moments of stupidity where you need to turn off your brain. I will say this year has been a notch above previous years in terms of quality though.
We've hit a sort of saturation point though with Blockbuster films. With the home market as developed as it is and theaters being a fairly lousy experience now. Why should people go for anything that doesn't look amazing or sound amazing? Most of the movies doing very well now having strong marketing(Ala Deadpool, Civil War, and Jungle Book), and every single one has generated lots of positive WoM online. You can't hide a dud film anymore, or even something that would have been serviceable 5 years ago isn't worth it anymore.
Since there are so many more competing forms of media. Either the marketing has to be on point or the Word of Mouth has to be A range. Jurassic World is one of the best examples of "Turn your brain off films", yet it still did bank. No more idiotic than any Transformer's film or ID4.
But people are less inclined than ever to go to the theater unless there is that sort of "Must See" atmosphere around it.