True, that might be the case; but with all the constant fan demand to have him appear in the MCU, the planting of Easter eggs alluding to his appearance, and how Tom Holland gets all excited and almost can't keep his mouth shut every time some journalist asks about the possibly of Peter and Miles teaming up in a movie, I can't help but feel its inevitable.
But you're right, with the runaway success of Spider-Verse, Sony may want to postpone that inevitability. Really though I think it ultimately comes down to what Kevin Feige and Amy Pascal are able to hash out when its time to renew their Spider-Man MCU deal.