Why is the statement that at a given point in space there is only an electric field or only a magnetic field is not accurate?

If the charges are stationary relative to the selected frame of reference, then only an electrostatic field arises in it around the charges. In another frame of reference, moving relative to the first, the same charges move, therefore, in addition to the electric field around the directionally moving charges, a magnetic field also arises. A permanent magnet creates only a magnetic field in the frame of reference associated with it, but in the frame of reference moving relative to the magnet, its magnetic field will change in time, and therefore, an electric field will appear in this moving frame of reference. Therefore, it cannot be argued that at a given point in space there is one of the fields, everything depends on the choice of the frame of reference.

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