I can't speak to your specifics, but I've interviewed people that would be my manager before. While I didn't have the final hiring decision, my input was valued

I can't speak to your specifics, but I've interviewed people that would be my manager before. While I didn't have the final hiring decision, my input was valued because the person hiring them was C-level, and not as knowledgeable about the function this person would be leading as I was in many ways, both because of their skillset/experience, as well as the level of interaction they had with the team. Outside of title inflation concerns where it may be useful, it's really an opportunity to get additional valuable perspectives.