Here's what I think is happening...
- Sony is anticipating this third iteration of Spider-Man to be a massive success, which I'm sure it will be, due to the property's tie to the MCU.
- Sony has been desperate to make an extended Spider-Man cinematic universe since their second reboot with Garfield in 2012. Fairly concrete plans were made to this end, and were definitely set up in The Amazing Spider-Man 2 l, but fell apart when it was met with resounding negative reception.
- But now that this third iteration is likely to succeed, Sony feels they can revisit a retooled version of their extended Spider-Man cinematic universe... just without Spider-Man being directly involved, at least for now.
- My guess is that there will be references to Spider-Man in these movies, and maybe even intentionally vaguer references to events in the MCU. This Sony universe will be its own thing, but could technically maybe kind of sort of exist in the same world as the MCU, just not overtly.
- I could see Spider-Man himself then showing up in one or two of these movies down the line, like in Venom 2 or a Black Cat movie or whatever, after whatever arc he has in Homecoming and Avengers 3 & 4 is complete.
Basically, Sony is DESPERATE to get involved in the superhero cinematic universe game. Disney has Marvel proper, Warner Bros. has DC, and Fox has X-Men/Deadpool. Even Paramount at least has Star Trek, Transformers, and Ninja Turtles. Sony has nothing, save for Bond, which they don't fully own and are likely about to lose. They need a franchise BAD, they own all the ancillary Spider-Man characters, so they're going to take their shot with what they have. I'm not endorsing it, just explaining where they're coming from. I seriously doubt it will work out well, but who knows...