- No one can clone them?
- They could license their code to partners?
- No one trusts them anymore.
- Partners go back to Android.
- The community, which significantly develops the code for them, can no longer help write code or fix bugs.
- As a result of #3, everything is now buggy, and they no longer have the resources to do much of anything.
- Ubuntu dies.
I'm not seeing any balance sheet on which they could possibly decide to close up the source code.