Very nice article. I am the collections manager (insects) at the Museum of Zoology, and a few years ago I catalogued hundreds of old b&w negatives that were made in the 1918-1930 period. They had not been stored in the best of situations, but were easily viewed and of course, could be printed or scanned. Since they were roll film negs, most of them could be easily contact printed. I have to wonder what will happen to images taken digitally today, 80 years from now. A physical thing is harder to lose than an electronic file (most of the time). I foresee people losing all kinds of images for a variety of reasons.
The other thing you bring up is ruggedness and reliability. There is no way any modern DSLR will be as rugged as say, a Nikon F2. Dust, sand, moisture, are all the things that will befall photographic equipment on a site; coupled with the need to have all the infrastructure that digital requires, working in remote and inhospitable areas really makes film a better choice. Someone will point out that once you have your images on a chip they are safer than film with latent images. Maybe. I think of the Shackleford expedition as a case in point. A Kodak vest pocket camera recorded some amazing images from that near-disaster. No batteries. Just film and a dry pocket (somewhere).