Hollywood was covering World War II in blockbuster movies as late as the mid-70s. About the only reason I can think of for ignoring Leyte is that it violates the commonly-held narrative that the Pacific War was “won” at Midway, which of course is wildly incorrect.
All films about WWII were like the “Combat” series.”Cha-kee”, “Cha-kee”, Kirby, take that ridge...”
One film IMHO is one of the best, the 1949 12 O'clock High with Gregory Peck.
In any event, the style, genre and stories about units or GIs made a radical transformation with “Saving Private Ryan”.
Perhaps Leyte Gulf” was too much of a “Turkey shoot” to be shown as PC fair and balanced with both sides fighting moral dilemmas...?