Disney has made the decision to no longer release catalog titles from its own vaults as well as recently acquired 20th Century (Fox), according to a report by The Digital Bits.
All power to Disney+
Beyond new, major theatrical releases from Disney, Pixar, Marvel, Lucasfilm (Star Wars) and 20th Century Studios (née Fox), there are no plans to release catalog titles on UHD Blu-ray after the release of Home Alone next month.
That is, in essence, the rumor making the rounds. The company has not commented publicly on its plans but multiple retail and industry sources have "essentially confirmed" the situation, the report said.
Why? Disc sales continue to drop year after year and the company is now dedicating almost all of its attention and home entertainment ressources to Disney+ and streaming distribution in general.

Disney will continue to release catalog titles in 4K HDR but only through digital storefronts and Disney+.
James Cameron's Avatar may be the exception as Disney, after the purchase of 20th Century Fox, is planning to turn Avatar into a major franchise.
- Source: The Digital Bits