I don't embrace the idea that the best audience is the most ignorant. The mantra amongst many filmmakers including the late Sydney Lumet is that whatever technical decisions are made throughout a movie (in context, he was referring to lens choices) are meant to be invisible; the audience shouldn't recognize any changes in a film's visual approach, they should only feel it. Much like the theatre you're likely not watching the movie in, they'd prefer to keep you in the dark.
I'm not researched enough to know whether things have always been this way or whether it's some misdirected attempt at prolonging the elusive 'movie magic' effect, but it's a startlingly, almost insultingly, dumb inclination.
There is no scenario I can envision where a movie you admire loses some of its intrigue or power because you succeeded in identifying and decoding a visual motif. Being practiced enough to catch a developing lens strategy should not be a disenchanting event.
Some clarity: Narrative films ordinarily function on two levels; There's the story being told and the way it's being told. But the way goes beyond just story structure. The way includes all of the elements that make the cinema what it is.
What well-intentioned but unknowledgeable film goers tend to do is read into visuals symbolically, and even worse, on a purely subjective, usually superficial level; Red means extremity of emotion, be it hatred or love. A fractured mirror always precedes an unfortunate event or a troubled psyche. Too often, film goers assign objects a predetermined value.
Every movie hypothetically begins with a clean slate. Even genre movies with their recognizable motifs frequently aspire to misdirect or manipulate cinematic stereotypes. Objects in the frame, compositional decisions, musical choices and so on only gain true value as the movie progresses. A good indication that an item or directorial decision is worth consideration and dissection is repetition. Another is strangeness (counter-intuitively). A fade-in during a movie with nothing but cuts is likely a moment intended to be noticed.
These types of developments happen gradually but for some it never happens at all because they're not astute enough to catch them. Fortunately (or unfortunately), cinematic shrewdness is also gradual. It's important to remember that a movie is a movie. To not consider a movie in cinematic terms is not only a disservice to yourself, but a detraction from a full and complete understanding of a movie's intention.
Here's my proposition: Your favorite movie of all-time is likely better than you'll ever know if you happen to be cinematically illiterate.