Fluctuat nec mergitur
We've already gone over this. Star Wars was always part of popular culture, it was intended for mainstream audiences. Your video is also very selective as many critics loved it, Roger Ebert for example gave it glowing reviews:
In 1977, Roger reviewed "Star Wars," describing the four-star film as an out-of-body experience. He added, "The movie works so well for several reasons, and they don't all have to do with the spectacular special effects ... ["Star Wars"] relies on the strength of pure narrative, in the most basic storytelling form known to man, the Journey."
There's always a certain disconnect between professional critics and audiences, but the fact remains that Star Wars immediately struck a chord with regular movie goers. I still remember my father being quite blown away by it. Star Wars laid dormant for almost two decades, it would not have survived such a long hiatus without being recognized from the start.
40 years later everyone remembers The Empire Strikes back, but no one remembers other 80s sci-fi movies like Alien Dead, Galaxina, or Death Watch. If you look more modern to something like 1998 a movie like Armageddon or The Big Lebowski can be consider a "classic" now while stuff like Phantoms or Soldier (a BLADE RUNNER spin off) are more forgotten.
The fact that the original Star Wars spawned so many copy cats flies in the face of your assertion that Star Wars was trashed. People automatically recognized its cultural impact otherwise they would not have tried to recapture the same lightning in a bottle. Also many of those copy cats have become cult classics of their own, such as The Last Starfighter and Battlestar Galactica.
So many movies during that time laid the foundation for several genres, like Mad Max, Indiana Jones, Drity Harry, The Thing, Bond, Terminator, Space Odyssey, Shining, Steve McQueen and Bronson movies. Many of those had instant cultural appeal as they presented something new, something that the audiences had never seen. Nowadays these movies are few and far between, during the golden ages they were a lot more common.
I'm sorry but that argument is just way too simplistic. Most classics have struck a chord with people from the very beginning. Also you've failed to explain how new classics can be created when so much of today's cinema are remakes and sequels.