Having the prebuilt client and art assets you hack and change on saves you million of up front cost.
The foldingideas videos about decentraland talks about this. "Dead" mmorpgs work on a small skeleton crew despite the original game having taken 100s of people years to make. Looking it up the turtle wow server was like 5-10k concurrent players? A lot for sure but bordering on that category.
It takes a lot of work to manage that but nothing compared to making an original IP from scratch.
I wouldn't be surprised if this is not the last we hear from them. The server itself is not based on proprietary Blizzard code so they could keep using it and they already started developing their UE5 client. Maybe they will go the full way, create their own art assets and relaunch as TurtleMMO in the future.
The foldingideas videos about decentraland talks about this. "Dead" mmorpgs work on a small skeleton crew despite the original game having taken 100s of people years to make. Looking it up the turtle wow server was like 5-10k concurrent players? A lot for sure but bordering on that category.
It takes a lot of work to manage that but nothing compared to making an original IP from scratch.