I believe will function a lot like Rust or Ark/Conan exiles..
Imagine World of Warcraft or Elderscrolls Online, etc. With a PVP and land building system as Rust/Ark.
Another thing is that exploration NEEDS to be a very high factor. No randomly generated environments..
2020 internet speeds are a lot faster, technology is better.. This type of game would be really addicting IF DONE RIGHT. A triple A company such as Blizzard, Bethesda, or Bioware should do this..
I'm telling you it'd be fire af. But not everyone would be into it.. It'd work. It just wouldn't be the carebear grind experience that most MMO companies are catering too.
(Also non related the Battlefield series developer DICE should make a medieval fantasy type game.. Dragons as planes, naval combat with cannons... Cool classes like mages and necromancers, etc)
I'm telling yoouu....