Consider this: How can one equate that which we know to be God-breathed with that which can only be the traditions of men? Even in the fetid swamps of Romanism, their traditions are not 'God breathed'... Yet they assume to lift them equal to, or even above that which is known to be of YHWH.
SOLA-scriptura does not mean ONLY. ALL Protestants have their own traditions, ALL Protestants listen to and learn from other sources, but sola-scriptura dictates that nothing learned elsewhere can hold an equality or superiority to the written Word. And rightly so, for if it is OF YHWH, how could it possibly differ from what is written?
That's the Catholic position regarding the place of Scripture as a source of revelation.