Avengers: Infinity War had quite the dramatic cliffhanger, but it may wind up making things difficult for marketing other films in the Marvel Cinematic Universe. (Warning: spoilers to follow!)
The movie ends with the snap heard ’round the universe, leading to the sudden end of half of all life. Among those whom we see die are Spider-Man, Black Panther, Doctor Strange and all of the Guardians of the Galaxy except Rocket (and Gamora, who had already died).
You might notice that these examples are all newer heroes who have sequels coming up in Phase 4. This may have been a bad move on the studio’s part, because it makes it even more obvious to fans that, despite several statements implying otherwise, these characters are going to come back. Unless, of course, Marvel Studios is planning to cancel basically every MCU movie that they’ve announced to come out post-Avengers 4.
Reportedly, the sequel to Spider-Man: Homecoming is already in the works, and is set for release about three months after Avengers 4. That obviously means that it will need to start filming relatively soon. The same goes with Guardians of the Galaxy: Vol. 3, which is expected to begin production sometime early next year.
What all this means is that, essentially, Marvel Studios will have to admit that these characters are coming back before the Infinity War sequel officially resurrects them. Which, to be fair, will not be too much of a surprise for anyone, as we all expect them to come back somehow anyway.
Perhaps it would have been better for the studio to have killed off Iron Man, Captain America, and the other heroes whose actors are planning to leave the franchise soon anyway. Then again, it also makes sense to keep them around as the protagonists of the next film, letting them have one last hurrah before the younger generation takes over.
It is interesting to compare all this to the MCU’s rival franchise, the DC Extended Universe. It killed off Superman in its second movie, Batman v Superman: Dawn of Justice, but barely tried to hide the fact that he was obviously going to come back for Justice League. As in that case, the only question was how; after all, in (movies based on) comic books, nobody stays dead for long.