I doubt confiscation would occur but asset and price controls are likely as the last defence against deflationary collapse
All the gold in India is not going to do you much good in Austrlalia if you cant get it out the country
Golds only unlikely to go unregulated in India because its still a currency there , you trade gold in any village in India, try doing that any capital city in Australia.
Same with the arabs there are many societies where gold is still an intrinsic part of daily life
Sure black markets would certainly exist but a bag of gold down to the pub doesn't fill me with confidence
In a collapse scenario how many of your fellow citizens are going to march in the streets with pitch forks if gold was regulated? I would bet 90% of voters wouldnt care less.