It's sardonic rather than ironic - irony is sarcastic humor devised to highlight a contradiction or hypocrisy; while sardonic is disdainful, bitter and scornful.

It'd have been ironic if Anthropic had asked the applicant not to use AI for the sake of originality and authenticity; but if the applicant felt compelled to do so, then it better rock and wow them to hire the applicant sight unseen.

It's sardonic because Anthropic is implying use of AI on them is an indication of fraud, deceit, or incompetence; but it's a form of efficiency, productivity or cleverness when used by them on the job!