I think it's mostly a consequence of measuring squads by total value. Ukraine have two goalkeepers valued at 25m, which obviously inflates their squad value relative to how strong their performances can be, because one of your 20m+ players is always on the bench. Also, and probably more importantly, the total squad value is very skewed by singular expensive players. Look no further than Norway, notoriously an unremarkable performer, but their squad value is over 500m because Ødegaard and Haaland are worth 110m and 180m respectively. Those two alone are worth more than the entire Japanese squad.

It's obvuously not a clear-cut indicator of performance.