According to the information contained on the Steam Seewang website, using the data present on the network on the night september 15, 2020, the day of the last page update, it would be necessary to disburse approximately U$541,200 to guarantee every game in the library at full prices.
With active discounts, the total value would drop to approximately U$528 thousand.

Its not absurdly expensive, but, still… A lot of money to buy games that most of them you’d never be able to play.