Slop.

All works reference older works.

No shit. You still shouldn't rely on references as the primary carriers of meaning when you have a point to make unless you're writing for a very narrow audience that you know will get those specific references. You shouldn't be relying on your audience recognizing a name as derived from a minor greek god, or that you're structurally paralleling a book that's on high school reading lists, or expecting them to have a grounding in 19th century cultural associations between symbols and colors for them to understand what you're saying.

Shakespeare

Shakespeare was writing slop for hogs in a vulgar dialect. He was literally meeting the public where they were in language they would understand and packaged with fart jokes they would enjoy.

a CIA plant when he rmade references to Greek and Roman mythology.

Remember that I said that symbolism, allegory, and allusion are fun little treats, they're something to fill out and reinforce a work or add foreshadowing. What I am criticizing is the practice of hiding one's point behind them, of secreting it away in a post-truth realm of free interpretation where anyone can reasonably argue you're trying to say whatever they want to imagine your point is.

If you have a point to make, it should be blunt, textual, and preferably repeated and symbolism etc should enter in as additional layers beyond that rather than instead of that.

Right, so make that 'elite education' available to all so it's no longer 'elite'.

You're still going to have people who bounce off of it, or don't retain all the mountains of possible works or concepts, or who don't enjoy the process of unraveling the special smart-lad puzzle box you've crafted, and you still can't get around the intractable fact that if the meaning of a work isn't textual it may as well literally be whatever bullshit any given reader claims it is.