@Tim ETTR makes sense when we talk about digital photography, because we can generally assume that the photometric response of the sensor is linear until we hit cipping. In such situations, we want to maximise the signal-to-noise ratio by increasing the signal across a more-or-less constant noise floor. We can then adjust the gain digitally in post-production and apply a saturation curve as appropriate to the scene.
In the case of film, the characteristics of the film emulsion are fixed, and so it becomes much more important to set the exposure in-camera so that the key midtone aspects of the scene lie within the latitude of the film. In this case, we still want to ensure adequate exposure to avoid having to “push” the film too much during development, but ETTR itself doesn’t make as much sense.