The Astros-Phillies was the least watched World Series on record, according to Sports Media Watch except for the neutral-site 2020 World Series during the COVID pandemic.
The six games averaged 11,784,000 on Fox, down 1.3% from the 11,940,000 for the Atlanta Braves' six-game win over the Astros last year and ahead of only the 9,946,000 for the Los Angeles Dodgers' six-game victory over the Tampa Bay Rays in 2020.
The 12,550,000 viewers for Game 6 made it the least-watched Game 6 on record, according to SMW. The UGA-Tennessee game beat all six World Series game telecasts. And this was still the most-streamed World Series in Fox history.
TV viewership has steadily declined over the years. The graph below shows the average rating (in percentage) and average number of viewers (in millions) for each World Series since 1973.