Much more difficult than buying bitcoin. To get bitcoin all you need is an ATM. To buy gold you need to go to a vendor and make sure the thing you're getting is certified. Then you need to carry it home safely. What if you get mugged on your way home? They won't steal your bitcoin, but they could get your wallet and that ounce of gold you were hiding there.

To sell it, technically you just need to go to the same vendor. The problem is that you can't really move it around. For instance you have to declare it at the airport and there's a limit on how much you can carry. Forget about taking a million $ in gold through customs. They'll need all kinds of paperwork and will ask you why you're taking it to another country and what you're planning to buy with it.

Bitcoin is something you can move around at will without anyone knowing about it.