I think Shikamaru would make a good Hokage if he chose to do so but he wouldn't do so. He lacks ambition. He's like his father and Asuma in that way. Neither of them wanted to be Hokage. They would protect the "King" in their own way as Asuma did. His intelligence and his capacity to understand people's strengths and weaknesses will make him a great advisor like his father. I think being Hokage is more work than he would like to take on.
If Kishimoto wrote it, then it is not BS. The guy who creates the rules and and entire universe we are watching, thinks he would be a a great Hokage. So maybe we should change how we think about Shikamaru. Kishi is telling us something.