One of the problems is that mainstream cinema and TV is more plot-driven than ever before and that has led to a certain amount of paranoia on the part of the filmmakers. Spoilers are now guarded to the extent that actors auditioning for a role have to sign non-disclosure agreements, and trailers similarly try to disguise anything that, to mere mortals like me, might seem meaningless.
Indeed, the Marvel Universe engineers acts of subterfuge to put fanboys off the scent. Avengers: Infinity War’s trailer even went to the trouble of actually inserting the Hulk in order to disguise a crucial plot point.
The Marvel fanbase is insatiable, and the producers know they have to fulfil certain obligations to get them talking. This is unusual, though, and few films could get away with misleading their audiences to this extent. I remember the case of Kangaroo Jack, a critically mauled crime caper from 2003, the trailer for which focuses mainly on a talking CGI marsupial.
In fact, the benighted kangaroo only appears in one hallucination sequence, and audiences were left feeling ridiculously short-changed, or wondering whether they had accidentally dropped some acid.
