You are merely describing
how the structure was determined by algebraists, not the reason for the structure itself.
Here's an example. Michelangelo carved his
David out of marble. The structure of the young man was not inherent in the marble itself.
The
Venus de Milo was discovered by a Greek peasant two thousand years after it had originally been sculpted.
This is not to denigrate the work of the algebraists. Their work is incomparably more difficult then digging up a field on an island in the Aegean, but they did not shape the group whose structure they described.
Another sculptor with another block of marble could produce a different sculpture than
David, but anybody else would have discovered the same
Venus de Milo. And even if they hadn't discovered it, it still would have existed!