Honestly the portable column is debatable. One ounce of gold is lighter than a wad of $20’s in cash to reach $2k (and much smaller).

If the fiat is in hundreds they are comparable though. Most people are not carrying around bars of gold bullion which is probably what they are referring to in this.

Bottom line if someone needs to travel and bring money, a combo of all 3 is prudent (at least until fiat is so debased that it takes up too much space lol)