Except that all grains are the same size, whether they belong to a sheet of 4*5 Provia, or to a 24*36 roll of the same film.
Pixel size does obviously differ.
Is changing pixel size like changing the type of film?
I thought, all things being equal, like pixel size, then a bigger sensor seemed better than a small one, like 4x5 Velvia 100 is better for detail than 35mm Velvia 100. It gets a bit trickier when you change more than two variables at a time - 4x5 T-Max 400 and 35mm T-Max 100.
I have heard that digital is not electronic film, but it seems there are many similarities that tie film and digital photography together. Digital is not all new.