You can't understand Zizek, or Zizek's "strategy", if you approach it in so straightforward a way.
And that's the point.
It's not "average" people who are being "kept away", it's enlightened people who are being filtered for.
By "enlightened", of course, I do not mean the Zen notion, or any such thing, nor do I even use the term normatively; I only mean that those who have independently had the experiences and reached the understandings necessary to apprehend what Zizek is saying, will be able to do so. That is the filter. If Zizek explains to you in plain language what he is saying, you may understand it; but that is counterproductive, because if you need his points explained to you in plain language then you are not the sort of person he is speaking to.
Conversely, if you listen to Zizek and do not understand him, you may later have the relevant experiences and reach the relevant understandings, and apprehend his points retroactively.
Many things work this way.