There are still quite a few native 70mm films that are not available on HD/UHD disc in the U.S. that were only released on DVD and other previous formats or not at all (I'm not including 3-camera Cinerama films). These are among the best-looking movies on celluloid ever made, yet they have not appeared on the premium HD home video formats, and the HD format is now 19 years old!

It's not getting any cheaper to restore and transfer these films to disc, and it has long been exorbitant costs standing in the way. Part of it is that these high-resolution films need to be scanned at 8K. Some have even disappeared (The Big Fisherman - Super Panavision 70 1959 - Disney): I've read that Disney has flat out said they will never release it. I assume it has to do with costs, which is somewhat understandable considering the potential return on investment (high six to 7 figures costs).

List of extant English language native 70mm movie studio films only on DVD (and/or lesser formats, or not at all):

Around the World in 80 Days (1956 - Todd-AO 2.20:1) Released on pressed Warner DVD in 2004. Newer releases are DVD-R.
Raintree County (1957 - MGM Camera 65 2.76:1 native AR (but never shown in that ratio publicly) Released on Turner double VHS in 1990.
The Big Fisherman (1959 - Super Panavision 70 2.20:1) Buena Vista. I've only ever seen 4:3 TV prints, an irresponsible travesty for a 200-billion-dollar company.
Porgy and Bess (1959 - Todd-AO 2.20:1) Samuel Goldwyn Productions. Unavailable, controversial, and languishing as far as a proper physical release goes.
Can-Can (1960 - Todd-AO 2.20:1) Twentieth Century Fox. Released on 20th Century Fox DVD in 2007
The Alamo (1960 - Todd-AO 2.20:1) United Artists.162-minute cut released on MGM DVD in 2000. 70mm Toronto print (172-minutes) released on MGM/UA Laserdisc.
The Fall of the Roman Empire (1964 - Ultra Panavision 70 2.76:1) Released on Genius Products (Miriam Collection) 2 and 3-disc DVD editions in 2008 in 2.35:1 AR.
Cheyenne Autumn (1964- Super Panavision 70 2.20:1) Released on Warner DVD in 2006. Looks good.
Lord Jim (1965 - Super Panavision 70 2.20:1) Released on Sony Pictures DVD in 2004. Pretty soft looking for a 70mm source.
Star! (1968 - Todd-AO 2.20:1) Released on 20th Century Fox DVD in 2004.
Mackenna's Gold (1969 - Super Panavision 70 2.20:1) Some scenes filmed in 35 mm are blown up. Released on Sony Pictures DVD (4:3 AR!) in 2000, though there now is a widescreen release on DVD.
Ryan's Daughter (1970 - Super Panavision 70 2.20;1) Released on Warner 2-disc DVD 2006. Looks good.

I didn't include Super Technirama 70 shot films since those were shot on special larger area 35mm film (horizontal) and blown up to 70mm. They also look much better than 35mm shot films and also translate well to home video when done right. This is an initial list and additional information is welcome.

"Around the World in 80 Days" used the Todd-AO 70mm process with an aspect ratio of 2.20:1, and the Warner DVD benefits from the large format film elements, but the film has not had extensive cleanup. Stock footage suffers most. This is generally a pleasing replication for the DVD format and its limitations. It suffers little on large screens for a DVD, again, due to the higher resolution of the film elements.
The 5.1 soundtrack seems to be a new mix. I noticed stereo effects in the surround channels, such as when the horse-drawn firewagon goes by to the right of the screen into the right surround channel. As far as I can tell, surround channels were mono in the 1950s and 1960s. The soundtrack is effective especially as the screen widens after the Edward R. Murrow prologue, and the rocket blasts off.
This film was originally shot at 30 frames per second for the 70mm version, as was "Oklahoma" the year before.
There has been information at some other sites that "80 Days" is being restored by Warner for DCP and home video, and if "Oklahoma" is any indication, "80 Days" will look fantastic.

Raintree County (1957) was the first film shot in MGM Camera 65 (later known as Ultra Panavision 70) with an anamorphic un-squeezed aspect ratio of 2.76:1. There is no indication that it was shown in the 70mm aspect ratio theatrically, only printed down to 35mm. Civil war scene footage from Raintree County was used, and shown in the larger format, in the 1962 film How the West Was Won (below) which was in the 3-panel Cinerama format.



After a double pack VHS release in 1990, this movie was last released on Laserdisc in 1994.

The only one of those films I've re-watched recently is MACKENNA'S GOLD, when it ran on the Western Channel a year or two ago. Not a good movie, but I can see why I enjoyed it on the big screen when I was 15. What I appreciated this time is how much fun Omar Sharif, Julie Newmar and Camilla Sparv are having with their roles. (Contrast that with dour Gregory Peck, who later called this film, "A terrible western. Just wretched.")