As much as I would prefer a good Fantastic Four movie to a bad one, if this movie tanks super hard, what are the odds Fox might make a Sony-esque deal with Marvel in time to see Doom get a post-credits nod and/or easter egg in, say, Black Panther? Really, I don;t think the MCU needs Spider-Man, but I feel like they're really going to need Doom once the Infinity War has run it's course.

Anonymous
I think it was a million-to-one shot that this happened with Spidey, so hoping for a repeat with FF or X-Men is longer odds than winning the lottery–not absolutely impossible, but damned unlikely.