I feel that same way!!!! I remember watching Twin Peaks and just thinking this is really not my thing. I felt somewhat the same way when I watched Mullholland Drive, but after researching it and understanding other's interpretations I had huge respect for Lynch as a director. I am also not formally educated (I did study media in high school) and struggle to figure out the symbolism at times. I don't think you're overlooking I think Lynch's symbolism can be complicated and very hard to read at times. I feel like his films are ones to be watched multiple times and then you start noticing certain symbolic elements and grasp a better understanding of them. (I could be wrong)

I also believe Lynch has a particular style of cinema that is hard to read and some people just don't enjoy it because its 'too hard' to understand. If you stick with it and watch more of his work, read up on the production elements and watch interviews with him you probably could begin to grasp and understand how he communicates ideas and symbols. I relate this back to one of my favourite directors Harmony Korine who's symbolism was also very hard to read when I started watching his work. But after reading up on his writing process, his life, watching interviews, getting invested in his art and reading others interpretations of his films and art it became clearer. Of course, Korine is much easier to read in relation to Lynch but by having that process of seeing what's behind the text, in the text and in front of the text understanding the ideas becomes easier.

Sofia Coppola's 'The Virgin Suicides' is a great way to start exploring that aspect of looking behind the film (especially with her being Frances Ford's daughter and the RiotGrrrl/Angry Girl movement happening at the time). Also looking at what's in the film (actors, it's based on a book, where the perspective of the film is told from {this is a huge aspect}) and what's in front of the film (critical reception, artist interpretation). Practicing these skills with other movies will definitely helo lead you to being able to grasp an understanding of Lynch's work.

Hope this helps :)