It seems strange that it hasn't been sorted yet, VM have the best internet platform by some margin and Disney have a channel or app available on most other platforms. I know that Sly have boxed off the 'channel' route but an app would seem to be in both companies best interests.
You can probably move to Sky but for some people that would bring more trouble than the benefit of gaining the Disney+ app.
For myself, in addition to my V6 I have a Fire TV Stick and a Now TV box. I don't think that I'm the only person to use three devices for TV and VOD, but if I want BritBox I can hook up an old TalkTalk Freeview box I happen to have, but this would start to look ridiculous.