Alt: A photo with the text "Would you press this button?" And two images representing options: option 1 is "50% chance of becoming a billionaire" with an image of a shovel full of money, and the other "50% chance of becoming this" being an image of Astolfo, a character from Type-Moon's "Fate" anime/manga/VN series noted for crossdressing as a cute girl, and is commonly identified as a LGBT icon.
money in a savings account generally looses value as it doesn't usually keep up with inflation or cost of living increases. Someone who invests in the stock market will probably do quit well on average, however the 1920s existed as did the recent fluctuations of 2008 and 2020-2021 which could lead to large losses. A billion is a huge amount of money, however can still be invested or spent irresponsibly.
Laws have changed since 1920, and even with 2008 and 2020 every ten year period will still see 10% growth from a diversified portfolio.
And even if 4.6 million doesn't buy what it did last year you can spend less than that for the compound interest to overtake inflation easily.