Bit of a lame argument as it's only worth what you sell it for. Brown of course didn't get the best price but if it were sold today at $23b then in 20 years time someone would be arguing that a loss was made because the future price of gold will almost certainly be higher.
True, they didn't and I believe their policy would have been to let it fail costing many their life savings and several thousand their jobs. Not to mention the knock effect on other banks and confidence in the money markets etc>