It doesn't matter. Use interaction in your work if it inspires you, if it helps you, if it makes your work better. Don't feel obliged to. It's just one of the many colors on your palette.
And don't worry about definitions. That's a job for the critics. We need to give them things to define.
For myself, and perhaps along the lines of your references to Zen and Tarkovsky (but also
Duras), I strive towards the absolute nothing. The less there is in a game, the better the game is. It's a sort of purism, yes, but a very directed purism. I want to achieve a certain impact. And I believe the impact is maximized when the means are minimized.
Maybe because it makes the player work harder, do more themselves. Of course a balance needs to be found to invite the player in, to make them want to make the effort it takes to achieve aesthetic ecstasy. And that's where interactivity can be very powerful. The artistic experience is something that happens in the viewer. And interactivity can help us help the viewer create this experience for themselves.