I could be real cynical and say Chase left an open ending in case his career in a year's time is looking grim and he can always revisit it.

If he did, if he were to make a film of this, and have Tony in it (which would be essential), then it defeats the entire purpose of that ambiguous ending, the whole tone of that final scene. Unless the purpose of that scene was commercial and not aesthetic.

For the record, The Sopranos shouldn't be brought to a cinema. The structuring of films rarely sits well with TV-to-film spinoffs. And I think it would be somehow demeaning to television as a medium, as if the whole show was a platform, a basis, to work our way up to a film. Notice how many TV shows are made into films, but how many films are made into TV shows? Exactly: not many. That's not because Film is in anyway "better" than TV, but I think a lot of people treat it so. Like, if there's a film made of it, it is somehow more immortal.

TV and Film sometimes overlap, but they are fundamentally different media, and I think we should sustain some sort of integrity for the uniqueness of both.