Hiruzen is yet again trolled...

[startup97]

He used all 5 Elements to an A Rank level simultaneously with one hand seal at old age. No one else can replicate that except the Sage.

 

[EmotionalRockfish]

If anyone read the page explaining the profiles, they'd know that the chakra natures are only the one's Shinobi can handle. It's stated with a little asterisk that they're only guesses based on combat experience to this point and that their ability is always changing.

My guess, the chakra nature's someone has shown + the chakra natures they are capable of using, but perhaps not now. Sandaime's learnt all of them, others have yet to.