Yeah. I was originally viewing on my phone so the resolution difference didn't look as noticeable.
For a fairer comparison I've dug out a 1080p screen for Yakuza 6 that's fairly comparable to one of the new Shenmue screens.
Compared to:
I still think that all things considered, Shenmue III holds its own.
If anything it certainly highlights the differences between each series visually, because there's a lot going on in that Yakuza screen to make the environment more flashy (wet pavement, a lens flare effect on the distance street lights, steam coming from...?). Whereas Shenmue III is distinctively more earthy in part thanks to its more rural setting, but also because there are secondary systems that affect the aesthetics of the environment - like the real time weather system which may or may not have rain causing a similar wet pavement look on any given day.
Funnily enough, a filmmaking trick I know to make urban outdoor scenes look better at night, is to wet the pavement with a huge amount of water, then spread it across your shooting space with a broom. The water catches the light (either ambient/practical, or from your own lighting rig), and makes the scene look more "textured".
That's kind of how I feel about Yakuza visuals vs Shenmue visuals. Yakuza deals in very well constructed film sets, Shenmue attempts to create living, breathing worlds.