That fantasy world is there for entertainment. Frankly, I don't find a 4 decades long, played out story to be even remotely entertaining. Judging by the current poll results, I'd say that's a common feeling. That fantasy world exists so that new stories can be told, not rehashes of 40 year old 616 stories, not so a new continuity exactly like the 616 can exist. The argument that real life relationships can last 40 years ergo a soap-opera relationship (and that's basically what it amounts to) must do the same is without merit.