No cleaning method should be transferred to every disposer merely because it uses a familiar household item. Use ice only if the exact manufacturer's instructions approve it and explain the quantity and operating method.
What the observation tells you
Ice is not a universal cure for a jam, weak grinding or a restricted drain. A claim that it sharpens blades also misdescribes many disposer mechanisms. Do not add hard material to an appliance that has become noisy or stalled.
A useful next step
If performance has changed, identify that problem first. Approved routine cleaning belongs to an otherwise suitable appliance, not to experimenting with a fault that needs assessment.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.