We’re talking about degrees of friction here, from the essentially impossible (changing to a licence that doesn’t require attribution), to doable (changing to a non-sharealike licence). The key point is that the target licence needs to implements a compatible subset of terms of the input 3rd party licences.
So for example as long as a new licence required parallel distribution if you are distributing a DRMed derivative I don’t see an issue with maintaining the current waivers.
Sure (I’ve actually suggested that the board does that for the elephant in the room), but somebody has to execute on it and not give in if it isn’t forthcoming.