I don't know about the delay, feels like at worst it might be a short delay, like 4 months. They seem to have much of the pre-production sorted out, specifically the lore and worldbuilding, maybe they're just shaping up the actual story and characters, but the most demanding part of creating the universe sounds like it's almost done.
I wonder how big the team will be. I imagine something like 10-15 full-time guys, plus a lot of part-time people doing stuff like writing, etc. Doesn't seem so impossible, there's tons of extensions made for Unity that can really speed up work, and developing for just one platform will help a lot.