All else being equal................ what might the cost difference be between renting the equipment to shoot digital Vs renting the camera, equipment and costs associated with film.
Similar...2x ... 3x to shoot film.?
I have the impression that it is actually not more expensive to use film. As
@cmacd123 pointed out, digital requires more crew and higher rental costs. The storage media for digital are also quite expensive. The tendency to record and record and record with digital is something I have heard is very frustrating to some longtime actors and actresses.
There are various options with film, too, on the affordability scale. Using 65mm film is obviously more expensive than 35mm film. But 35mm film is the more traditional format. I don't think as many use old-school 4-perf anymore, unless they are recording with anamorphic lenses or want to use the old Academy ratio. I think it is more common nowadays to use 3-perf. And to make it even more affordable, you can record in 2-perf and still have nice quality. 16mm film, of course, makes it even more affordable and can still look quite nice.
Kodak Film Format Choices Infographic (PDF)
I think the main thing is that most people, unfortunately, just don't think of film as the true and best format anymore. People seem to accept constantly new technologies as inevitable and better, instead of understanding that sometimes the best is not the newest or most efficient or most convenient. I also don't have the impression that beauty and authenticity are very important to most people, nowadays.