Y en Digital Bits afirman que les han dicho que el proceso de meter Dolby Vision en los discos aún no está perfeccionado y tiene fallos y es el principal motivo por el cual no lo han metido en Guardianes 2.

As to the question some of you may be wanting an answer to, the reason there’s no Dolby Vision on the actual 4K Ultra HD disc for Guardians of the Galaxy Vol. 2 is that Disney simply wasn’t ready (from a technical standpoint) to commit to it on this first title. It’s not unlike the situation with Fox and object-based audio on their early 4K titles; the studio wants to make sure the experience they offer on the disc works well, is bug-free, and provides the viewer with the best quality. Disney is still evaluating Dolby Vision for inclusion on their discs and does intend to do so as soon as possible. Privately (and separately, from other industry sources, not from Disney), we’ve heard that there are still some bugs with regard to authoring and encoding Dolby Vision on 4K discs that are being sorted out. As the authoring tool set improves, this will become a non-issue