This is an extract from an Aussie FOIA decision, which clearly states it is the Person who is deemed VEXATIOUS, not the request

…completely opposite to the UK FOIA 2000 which states it is the request which must be deemed vexatious and not the requestor.

Introduction

12.1 The Information Commissioner may declare a person to be a vexatious applicant, either on the Commissioner’s own initiative or on the application of an agency or minister (s 89K).[1] A declaration has effect in accordance with the terms and conditions stated in the declaration (s 89M).

12.2 A decision by the Information Commissioner to make a vexatious applicant declaration will be based on the facts of the matter, after considering any application or submissions made by an agency or minister and any submissions from the person against whom a declaration may be made.