As Ms. Kamhi points out, the recitation of any theoretical justification for a position does not constitute a proof of its validity. This caveat certainly applies to her own argument. She can offer no proof for her theory because there is none; it is simply a personal opinion based on her own experience -which has no greater validity than the experience of anyone else.
No matter what sophistic gyrations Kamhi employs she cannot get around the fact that different people experience works of art in different ways. Any attempt to develop an accurate understanding of a cognitive basis for art would have to take all its forms into account-to consider all the evidence without making arbitrary exclusions based on personal preference. Anything less would be a "theory " that is more allied to fiction than physics.
The fact remains that some people find abstraction as meaningful and intelligible as so-called "mimetic" art. To exclude this reality is as absurd as excluding non-Euclidean geometry from mathematics just because some people find Lobachevsky incomprehensible.
Her statement that some people believe that abstraction should be immune to criticism is perfectly silly - no-one would take such a position just as no-one could consider any other form of art immune to criticism. Art cannot be addressed in generic terms- each work of art is a distinctly individual event and has to be discussed on that basis, otherwise we do get lost in pointless generalization-the truly meaningless abstractions of Ms. Kamhi's argument.