They were from a time before digital banking where all wealth had to be physically represented and were thus unable to amass anywhere near a billion dollar equivalent, let alone a trillion.
There are many people who tried to compare current day wealth to the wealth of historic figures. Those are, afaik, never about hard facts but a way of translating an estimation. This article names 8 trillionaires for example. They give ganghis kahn an estimated $120 trillion, and consider mensa musa so much richer they call his wealth uncrompihensible. You can find similar lists online, i guess the same names will take a similar spot on the ranking, but the numbers will differ. They tend to look at relative wealth (they estimate that Elon Musk has xx % of all money globally and compare that to the estimated percentage of global wealth of a historic figure and translate that to a current day value).
They were from a time before digital banking where all wealth had to be physically represented and were thus unable to amass anywhere near a billion dollar equivalent, let alone a trillion.
There are many people who tried to compare current day wealth to the wealth of historic figures. Those are, afaik, never about hard facts but a way of translating an estimation. This article names 8 trillionaires for example. They give ganghis kahn an estimated $120 trillion, and consider mensa musa so much richer they call his wealth uncrompihensible. You can find similar lists online, i guess the same names will take a similar spot on the ranking, but the numbers will differ. They tend to look at relative wealth (they estimate that Elon Musk has xx % of all money globally and compare that to the estimated percentage of global wealth of a historic figure and translate that to a current day value).