Why isn't Chess960 the standard? Bobby Fischer said that standard chess is dead and I believe him. Current players rely too much on engine-moves and theory in the openings and quite far in the middle-game without any real calculations, but memory. For instance, Carlsen had memorized engine-moves far into the middle game against GM Sergej Karjakin when playing white, which I find unfair.
Chess960 allows for 960 different positions to begin the game and no GM would be able to analyze every start to the current extent. Thus, Chess960 would rely on raw talent and calculations. Why isn't it the standard nowadays?
Chess players identify with their openings, all chess clubs have that one guy who always plays stodgy London stuff with white, the maverick with all his dodgy gambits and the youth player with 25 moves of Najdorf theory memorized for the day he finally gets to play it.

Opening books are by far the most sold type of chess book, and the number of titles is much larger than that of other types of book. People write hundreds of pages of grandmaster level analysis on a line that starts on move 6 and still lots of amateurs buy the books.

When an amateur watches a grandmaster game live, he uses knowledge of the opening played to understand what is going on. If they play a King's Indian and the center is locked, one of them is going to attack on one wing and vice versa. If it's a closed Ruy Lopez, we know there's probably a slow maneuvering game coming up, et cetera.

Playing memorized opening theory gives the amateur the feeling that for that part of the game at least, he is playing at grandmaster level.

In other words, chess players like opening theory.