I have a set of the complete works of Charles Dickens, printed in the year of his death (1864).
I agree, 50 years is young for documents.
Yep, and I've also been going through some old family books and papers: World Book Encyclopedia from 1935, handwritten college papers form the 1930s, and other books from between the world wars. All were just kept in boxes or on shelves, and are in very good condition, a little yellowed and a little dried, but still can be handled and used without damage to the paper.
Those 1961 BCs would be in excellent condition and could be handled and copied with no harm at all. The Hawaiian AG is spinning some tall tales, to put it nicely.
If the birth certificates are kept for the benefit of the public, why deny them at all? To deny them from the public renders them useless and going through the trouble of preserving them a waste of time. A state with policy that makes no logical sense is government out of control.