The impact of academic inbreeding on research productivity remains unclear. This study examines a critical yet often overlooked distinction: How the link between inbreeding and publication activity differs when academics' primary focus is teaching versus research. Focusing on highly productive Russian PhD holders, our findings reveal a complex picture. For research-focused academics, inbreeding is related to greater accessibility of different resources to achieve international visibility and recognition via international monographs, and to the greater teaching and administrative workload. For teaching-focused academics, inbreeding is associated with lower publication activity in the top-tier journals and higher publication activity in lower-quartile journals. We observe that mobile teachers have less access to the resources of the academic system, which may be seen as a factor of their lower productivity. Our study challenges simplistic views on academic inbreeding, demonstrating that its relationship with publication activity is multifaceted.