Closes https://github.com/ppy/osu/issues/29066.
Initially I fixed this at where the assert is right now:
9790c5a574/osu.Game/Screens/Ranking/ResultsScreen.cs (L333)
but because of the weird way that visible state management is done in
this screen that made it possible for the extended statistics to be
visible *behind* the score panels, without the score panels making way
for it. So this is in a way safer, because it prevents the visibility
state of the extended statistics from changing in the first place if
there is no score selected (yet).
This can be also seen in playlists, at least.
8dbd4d70ff