I’m pretty sure I remember Mike saying he would get this output on film - to make it easier to archive and preserve.
In my opinion, I’m not sure if film would be easier to preserve. The main problems people cite is how video formats change and how digital media storage mediums deteriorate. Let me tackle the latter first. Film also deteriorates—-look at how hard it is to get a good film print of Star Wars. You can alleviate the digital storage problem by just copying it listlessly to new storage devices. You can even try to checksum it to make sure you’re getting an exact replica of the original copy. (You can also do the same with formats and codecs) As far as I know, that’s not possible with film. So, I think most of this as possible should be done digitally.