There is also much more competition. While it's hard to get a singular number that encompasses all platforms, if we assume that Steam has had a relatively constant proportion of the user base over the past 10 years, according to Statista, the number of titles released has nearly grown exponentially.
Furthermore, the average price of a game in 2023 is just $15. I don't ever recall paying $8.50 on average in the year 2000 for video games; back then even the cheapest games went for $25, which would be equivalent to $45 today.