"many active and talented contributors, excellent project organization and discipline, and a focused community rallying behind one project"
The one project part is probably going to stick due to the high barrier of entry (some whispers have said that the reason CEMU is closed source is they used parts of the Wii U SDK that were under NDA to bootstrap development).
But the many talented contributors may be limited due to the closed source nature, and the culture of excellent organization and discipline might have trouble developing if the community is comprised of a few very talented developers focused on an emulator. Open source work allows people of varying quality to contribute, which can be a curse (if the overhead of filtering low quality contributions is too high), or a blessing, because people end up contributing to house keeping tasks that the core devs otherwise wouldn't have time for.
(and of course, this is all assuming it's not open sourced in the future)