The definitions we use to understand human nature are themselves more abstract and arbitrary than is commonly believed. Assigning such rights to AI could exacerbate the problem which already expresses itself in human inequality.
The metaphysical stipulations around human existence have been linked to mere tautological complexes that are often deeply entangled with racism and other forms of ontological elitism. Formal statements to the contrary, there are still legacies of the arbitrariness of these systems of meaning-making at play in politics today. The myopia of this kind of humanism is ill suited to address such ethics of the non-human as which pertains to artificial intelligence.