The metaphor is a simplification, in practice I think it is probably impossible to know whether you have achieved complete alignment. The question is then: how significant is the gap? If there is an emergent pressure across the vast majority of learning machines that dominate your environment to push you from de facto to de jure control, not due to malign intent but just as a kind of thermodynamic fact, then the alignment gap (no matter how small) seems to loom larger.
The metaphor is a simplification, in practice I think it is probably impossible to know whether you have achieved complete alignment. The question is then: how significant is the gap? If there is an emergent pressure across the vast majority of learning machines that dominate your environment to push you from de facto to de jure control, not due to malign intent but just as a kind of thermodynamic fact, then the alignment gap (no matter how small) seems to loom larger.