The Chinese have a reputation for cloning products and technologies.
I don't see it as being different than the J-20; there's lots of features on the J-20 that look like they were copied off someone else (stealth shaping, chines, DSI, lerx canard lerx delta formula), as well as stuff that's unique (anhedral-dihedral canard layout, railed sidebays) but when you put everything together it's a unique fighter.
Might as well say everyone copied from the Wright brothers’