Does anyone know why Stan Lee doesn't have a cameo in 2015's Fantastic Four? Was it scheduling conflicts? Did he not want to be in it? Was it filmed too far away? Was it another reason?
Stan Lee says they didn't ask him to cameo. Since they didn't ask, he didn't do it.
Here's an interview with Larry King where Stan says it was too far to get to at the time.
Unlike his appearances in the Marvel Studios-produced films, Stan Lee's appearances in the Fox films are less consistent. For instance, he did not make a cameo in 2014's X-Men: Days of Future Past.
For Days of Future Past, he explained:
STAN LEE: As a matter of fact I have never requested a cameo. I love doing them. I’m incredibly happy when somebody asks me to do a cameo but I don’t ask for them. In fact there are times I don’t get them. In the new X-Men movie, I don’t have a cameo because it was shot, I think, somewhere in Europe and I wasn’t able to go there.
But I have a funny theory about it; it also could be they didn’t want me to do a cameo because, without my cameo, the movie will make more money. You are wondering how and I am going to explain that. You see, somebody watches the movie and the movie ends and the person says “Wow, I didn’t see Stan’s Cameo. I must have missed it. So what do they do? Right back to the box office, buy another ticket, and watch the movie again. So I think it’s a big moneymaking ploy on the part of the producers.
Based on his comments above, and the fact that Fantastic Four was filmed entirely in North America, it seems that he simply wasn't asked to appear. (He explained above that if he were invited to make a cameo and the filming was not abroad, then he would appear.)
One could ask about his physical ability to make a cameo, given that he is 92 years old, but there seem to be no recent changes in his health — at least not reported ones. In general, he seems to be as sprightly as ever.
So it seems he wasn't asked by the director or producers, for some unknown reason — perhaps as part of the "ploy" he mentioned. He certainly got the OP wondering about it, and so maybe he is right!
While this is pure speculation, the lack of a cameo could be part of the deepening rift between Marvel and Fox (thanks to @WadCheber for this aspect) — see for instance:
It could be that the failure of Fox to extend a cameo invite to Lee could be a salvo in this dispute. Alternatively, it could be that a cameo was extended but Lee refused it, as a salvo lobbed from the Marvel side. We may never know.
It could be because the 2015 Fantastic Four was an abysmal film.
The earlier 2005 version had its faults, but had a fairly lighthearted approach that meant it could get away with it. By comparison, the 2015 version has few redeeming features. You only have to look at the Rotten Tomatoes score (9%) to realise that it's a dull turkey.
Someone suggested that the ultimate cameo would be for Stan Lee to walk in on Thor as a cleaner, casually lift Mjolnir, clean under it, put it down and walk out...