Jack Daniel
Legend
One of the simplest ways to resolve this (for WotC) is to do as 4e did: create a new license for 5.5 and not release the new stuff under OGL anything.
The GSL didn't need to 'unauthorize' OGL v1.0a because it was not relevant, and they left it alone for not-4e (i.e. 3e and 3.5) open content. No problem.
The big problems with that are 5.0–5.5 compatibility and the fact that Pathfinder exists now. Nothing like Pathfinder existed when the GSL scheme was dreamed up.
I'm convinced that this whole mess has come about because WotC is desperate to prevent the emergence of an OGL-protected 5.0-compatible fork of D&D à la Pathfinder that could potentially do to OneD&D what they believe Pathfinder did to 4e. And, to a lesser extent, to prevent 3PPs from using the OGL v1.0a and the 5.1 SRD to produce content compatible with OneD&D.
The only way to prevent these things is to nuke the OGL, and if that means going scorched earth on the 3PP ecosystem and wiping out Paizo and the rest of the competition as collateral damage, so much the better for them, they still get everything they want and more.