Like Humpty Dumpty, he can pay his words extra and make them work overtime. It is not very productive to argue about terminology. The real challenge is to find the explanatory paradigm that gives us the most useful results. If we define language as that which is produced by the human brain and articulatory apparatus in the configuration in which we currently find them, then we may be simplifying our work. We may never have to look at the output of an artificial intelligence construct or of another biological organism and try to decide whether it does or does not qualify as language.
Language is what humans do because language is what humans do'.
And if we get even a bit more concrete and decide that the wiring of the average human is the only system that qualifies as language, then even the ordinary output of some humans may be discounted as 'not language', if the brain configuration is significantly different. Successful survivors of infant hydrocephaly may be considered not to possess language, even though their speech is indistinguishable from that of 'normals'. For most of us, if it works like language, it is language. The physical details are immaterial. They could not communicate if they did not.