Should we compare new state with old state in the reducer

I am using spread operator in the reducer function, so what is happening when i am dispatching the action then it is creating new state (obj) even old state is same as like new state so it is re-rendering react component.

Is it good approach to compare new state with old state as object could be complex ? Deep comparison ?

const initialState = {};

export const reducer = (state = initialState, action: any = {}): any => {
  if (action.type === ActionTypes.RC) {
    return {
      ...state,
      ...action.config,
    };
  }
  return state;
};

Or redux does it out of the box for you in mapStateToProps ?

from Should we compare new state with old state in the reducer