At some point in 2030 this headline will appear: "We are now as far from Avengers: Endgame as Endgame was from Ironman." In 2049: "We are now as far from Avengers: Endgame as Endgame was from the fall of the Berlin Wall." To which everyone in 2049 will respond, "The Berlin what?" None of this will make me feel old because I will have been old for a very long time by then. Here's another one. In 2075: "We are now as far from Avengers: Endgame as Endgame was from the first Avengers comic book." This too will not make me feel old because I will be dead, assuming I don't live to be the oldest man ever. (Although, why not?)
My point is that I think the Marvel movies are some sort of high water mark. That they are going to stick in our cultural consciousness for quite some time. Unlike many of their contemporaries, I think they are pretty close to timeless. When looking to imbue greater gravitas to their action films, others have moved to playing pulled-from-the-headlines games and generating various woke forms of controversy; Marvel has stuck to the mythological basics. Yes, there has been a spot of virtue signalling here or there, but always in good taste and always subsidiary to the essence -- Heroism, Sacrifice, Justice, Vengeance, Faith, Hubris, Failure, Redemption -- all the existential qualities that have driven drama, and all the humanities, since time immemorial. If, in a few millennia, people look back on this era and interpret these films as indicative of our core outlook on the world, as we do with the myths of the ancient Greeks, I will say we did OK by Civilization and expect most eras will have done worse.
So yes, I am likely the last person you know to have seen Endgame. It now has, deservedly, the highest box office gross in all of history, displacing the execrable Avatar. It is different from the other Marvel movies, primarily because of the atmosphere. The trademark humor and repartee is still there, but the undertone is one of universal desperation. That tone was first struck in Infinity War when Cap says, "We lost."
There are three distinct parts. First is the Avengers actually avenging -- finding Thanos and killing him in retaliation for the snap. The second is triggered by a rodent of convenience, opening the door to time travel and the recovery of everyone lost in the snap. The third, in the best Greek tradition, has unintended consequences bringing about a new and larger battle with Thanos. Victory only comes, and redemption achieved, through the ultimate personal sacrifices. You could argue that this should have been two movies, which would have allowed a bit less hand waving around some character transformations that seemed to have happened in the interim (Hulk, Hawkeye) and maybe more on the state of the post-snap world.
I first started reading Marvel comics in junior high school as an outcast nerd, staring my teens in the teeth, scared and uncertain about my future. I would rush to the drug store every day just in case a new issue of one of my favorites came out -- twelve cents off the spinning rack -- my allowance permitted the purchase of four per week at most. I would read them cover-to-cover and over-and-over. I would visit flea markets to hunt down back issues. Now here are those stories and those characters again, this time at the top of the cultural food chain, with me staring 60 in the teeth, scared and uncertain about my future.
I don't know where Marvel is going to go next. I love Tom Holland/Spiderman so I'm sure I'll catch Far From Home when it comes to streaming along with whatever new Dr. Strange stuff is made, but the rest of what I have heard about "Phase 4" sounds like they are moving into a Marvel era that I am unfamiliar with -- one that came after my early teens -- so I'll likely feel less a compulsion to keep up on the new releases. I have no doubt they will be good and may affect a later generation as strongly as the last ten years have affected me. More interesting to me are the TV show plans.
Whatever the case, it's been a wonderful, uplifting gift having this mythology bookend my life so far.