Talk to Dermatologist on Seeking Consensus: Diagnostic Approach For Chronic Refractory Papulonodular Nuchal Lesions (10+ Year History)

I am seeking general diagnostic guidance for a chronic, papulonodular skin condition located on the back of my neck/occipital hairline, visible in the attached photo. The lesions (firm, slightly raised bumps) have been present and spontaneously waxing and waning for approximately 10 years. Previous consultations have resulted in presumptive diagnoses and topical/oral treatments (antibiotics, steroids) that provide temporary relief but fail to resolve the issue long-term. Given the chronicity, refractoriness, and potential differential diagnoses (e.g., Acne Keloidalis Nuchae, Chronic Folliculitis, Prurigo Nodularis), my primary concern is the lack of a definitive diagnosis. What is the consensus on when a punch or excisional biopsy is definitively indicated for a long-standing lesion of this type, and what specific differentials should be prioritized prior to escalation to surgical management?