The correct comparison would have been to have a stack of ~500USD on the right side, but that doesn't convey the pro-gold dogma as clearly.
If inflation metrics were accurate. Wouldn't there be $1700 stacks on both sides of the table?
One potential explanation for only $500 on the right side is inflation metrics being under reported. The way unemployment and virtually every other vital statistic has been under reported for decades.
I don't think you can justify saying that the price of gold has not actually changed between 1933 and 2020 (after adjusting for inflation in all parts of the economy, not just normalizing against CPI).
Gold itself is inflationary too, so if anything its price would have decreased. Keep in mind that the right side being $500 simply means that in 2020, you would need $500USD to buy 1oz of gold at 1933 prices (~20USD from 1933 = ~500 usd from 2020).