They aren't forced into canon. They will be canon. The new Spider-Man film is part of the MCU any spin-offs of it by proxy are as well.
Yeah... that's a huge issue. Hopefully those movies get canned ASAP.
I have faith that Feige knows what he's doing, though. Maybe S6 will be canned and Venom will be rolled into a Feige produced Phase 4 MCU flick. I'm sure the last thing Disney wants is Sony releasing competing MCU films at the same time they're dropping a movie.
So is Amazing Spiderman 3 still coming or is this really it for Garfield?
Already canned.