There are spoilers in this article so if you haven't played the video game yet and plan to, maybe hold off.
Yakuza 6 is a really interesting game to me. In hindsight it seems like a turning point in the kinds of stories RGG Studios is interested in telling. In particular the game goes extremely hard on ideas around parenthood, specifically fatherhood. But past that, and in conversation with the previous games in the series (including the "previous" Yakuza 0 and Yakuza Kiwami 2), it seems to be very interested in how the passage of time has affected Kiryu, and how hard he's struggled to actually leave the yakuza life behind.