Section 3(a)(3) of the license CC BY 4.0:
If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.
While it does not explicitly say so in the license, might 3(a)(3) imply that the person that shares the Licensed Material ("You") has to offer a way to be contacted by the Licensor?
Or in other words: May someone share my work (licensed under CC BY) without giving me the chance to request removal of (parts of) the attribution?