No. Removing a user-accessible reservoir is a maintenance action on that feature, not electrical isolation of the fridge-freezer.
What the observation tells you
The refrigerator and freezer can remain powered, and other components may still operate. Do not use tank removal as permission to work on lights, controls or wiring. The tank's own cleaning and refitting procedure must also match the model.
A useful next step
Follow the full appliance instructions for any task requiring disconnection and plan both food loads accordingly. Keep routine reservoir care separate from electrical or concealed-component servicing.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.