I would interpret your boss request as one or more of these things:
Your boss thinks you're not a self-starter. He may think you need to actively tackle issues without having to be asked. If so, possibly a production and effectiveness issue, not exactly a visibility issue.
He may think you're a reserved or introverted type and wants you to try and be a bit more open. Hence a personality issue, solving it strictly not for the benefit of work, as it's personal.
He wants his team to have more visibility and wants you to help with that. Not to make you stand out, but him, through his team. Asking you to do this for him. This time personal of his, rather than yours.
You have to interpret liberally what people mean by what they say. Nobody can explain themselves 100% accurately and we wouldn't go anywhere if we relied on 100% accuracy. Just as visibility at work active comprehension is a skill.