There's been a saturation of products in the entertainment industry over the past couple of decades which makes landmark "cultural defining moments" over this time pretty much nonexistent. It's all fast food cinema (even the wannabe "highbrow" stuff) where a movie makes headlines, gets Oscars, box office moneys & then kaboom, it's forgotten. You won't see another Apocalypse Now, another Psycho, another Taxi Driver. Too many movies/series, too many audience types with different interests/tastes & yes, a form of benign blasé attitude has set in where movies are really no longer that special anymore. It's like the moon landings, i.e. first time was "wow", the rest? (except Apollo 13 for different reasons) "it's cool, but boring now".
We see some movies desperate to jump out & make a cultural long-lasting impact & it's just not happening anymore (even war films like Dunkirk have been totally forgotten). Avatar is the same. Joker is on the same route, Black Panther is on the "who gives a fuck" list (Marvel's Expanded onslaught of a million movies/spinoff series keeps them relevant for longer) & the list goes on & on.
I read this one small anecdote about Kate Winslet who was hiking in the Himalayas, i.e. a really old guy approached her & said "Titanic!". Imagine someone approaching Sam Worthington in some random backend of the world & saying "Avatar!"? Nope. Ditto every other movie over this decade, tbh. It doesn't mean they're all shit movies, it's just the world we live in.