Faculty select teaching assistants and the research staff for their labs, effectively unilaterally. They have the power to hire and fire. They choose topics of research, and can instruct their mentees to stop a line of inquiry. This is similar in scope and power to a combined project-manager, research-manager and person-manager. They also are the decider to grant later-stage credentialing, so throw in a bit of training instructor too…
I work in industry.
Is my my tech lead an HR person? My manager? My VP? My Board? My majority shareholders? If not, why is a faculty professor an HR person?