And the F-15 is a copy of the MiG-25 because they both have two vertical stabilizers, two engines, and side intakes, right? In fact, let's call the J-15 a copy of the Su-30MKI because they look so similar!
For the sake of your common sense, or lack thereof, looks don't mean everything, especially in the field of aviation.
If you had done your research, you would know that the J-15 uses the same configuration, avionics, and base airframe as the J-15. The J-15 can be considered a J-11B with canards.
Every blind man calls the J-15 a "copy" of the Su-33, yes. Too bad some people aren't blind and actually do some damn research.