Neither is any other "foreign currency" which also needs to be "exchanged to local currency first".
See that's the thing the markets are trying to figure out right now ... is gold an industrial commodity? In which case, yes it is terribly overpriced! Or, is it in a time of world-wide currency crises reviving its historical role as a store of value, an AAAA++ rated, supra-sovereign "monetary asset" (rather than granted an immediate for-daily-barter currency) with no debt burden and no counterparty risk? If yes, it might still be vastly undervalued!
And we're talking about a country reserve, not exactly hand money.
My reply of "At the supermarket" is, I think, a succinct and correct response about the basic difference between currency and valuables. My local supermarket won't take US dollars either since I'm not in the USA. You know well enough that supermarkets in the USA do take dollars, and no supermarket anywhere takes gold (if you find one, let me know what it gives as change). The point still stands. If I'm wrong, I'd appreciate more information on why along with the down-votes.