This is a pretty good article covering the mess around the legal rights to Spider-Man, and what it means for fans of Marvel’s cinematic universe. Sadly, the bottom line is that Sony retains the rights to Spider-Man, and will make a bunch of movies in his world that aren’t part of the MCU, so Spidey will have one foot in the MCU and one out. Sigh.
And that doesn’t even touch the mess that is the X-Men. Double sigh.