16mm is about the equivalent of 2.5k (slightly higher than BluRay quality), so video wise, only the 35mm stuff ( A Hard Days Night and Help!) would benefit from a 4K visually (which has now been done for AHDN). Technically, it is possible to get a better picture out of the footage The Threetles interviews from the 1990's were shot on 16mm, the archival material used was a mix of videotape, 16mm and 35mm. But if they did re-edit and remaster The Anthology for modern audiences, you can bet that it would look slightly different to the current edit and watch this space for all the 'What's different in Netflix's Beatles Anthology' threads Paul, George, Ringo, and Yoko Ono Lennon all opened their own archives just for. Technically, it is possible to get a better picture out of the footage The Threetles interviews from the 1990's were shot on 16mm, the archival material used was a mix of videotape, 16mm and 35mm. The Beatles Anthology features over 1300 images, most previously unpublished. But the commercial benefit of a HD/4K upgrade would be to bring it up to a 2020's standard so it could hold it's own against other documentaries on today's streaming services. The main benefit for fans of a UHD 4K disc would be the Dolby Atmos soundtrack and nicer looking segments of the first two Beatle films. It would be a massive (see costly) undertaking.

To release Anthology in High Definition (or 4K), Apple would need to go back to the elements and remaster them individually. Bluray would be pointless (other than the soundtrack upgrade). The best format to watch the Anthology in it's current form is DVD. It was created in the 1990's with 1990's TV in mind. The master tapes to Anthology were edited on Standard Definition videotape. This has been discussed on here before (so excuse me for repeating myself) - The Beatles Anthology - 25th Anniversary Thread

The beatles anthology netflix