Is simplified writing/accessible tone frowned upon in publications? As someone who is just starting to read in the field, I found that most academic papers are quite 'stuffy'. They seem to use a great deal of complicated language and jargon needlessly.

I read Should academic papers necessarily carry a sober tone? and understand that jokes should be kept to a minimum but what about:


Simple language,
Metaphors/Allegories/Similes,
Casual language (speaking to the reader, using contractions, etc).


I think if you can contribute new knowledge to a field, and make it accessible to an 'average' educated user who isn't an expert in your field, then why wouldn't you?

Is casual tone unheard of in papers? Is it frowned upon? Do I ultimately need to learn to write in a more formal manner to get taken seriously in future works?
It depends on the intended audience.

There is no one rule for writing, academic paper or otherwise. You should always "mold" your content to the level of the average reader of the venue. 

Think Nature versus Scientific American, for instance. While I often read SciAm as an undergrad, I didn't really understand most of the Nature articles I had to read recently, because they are dense and full of acronyms that don't mean anything for me. Am I stupid? Maybe, but surely I'm not part of the intended audience of these specific papers. Clearly, both venues are different, one is more technical, the other is focused on scientific dissemination in a broader level. Submitting a very technical paper to a dissemination venue would be a bad idea, and vice versa.

From personal experience, even between technical venues, there is a significant difference. For my research, I alternate between heavily mathematical theory and applications. When I send articles to the IEEE VIS (or TVCG), the reviewers mostly skip the mathematical parts and expect a very "digested", non-mathematical analysis of the results. 

I recently sent an article to a more mathematical conference (ISMM), following somewhat the same format I usually use for VIS, with a more detailed mathematical section, but with the same "digested" analysis afterwards. While the mathematical part was accepted mostly as is, the analysis part was heavily criticized, for being "vague" and mathematically inaccurate. It was my fault, I didn't fully mold the content to the venue.

EDIT: Let me more clearly phrase my point: Sometimes reviewers will complain that the paper was too accessible. My example was exactly that, by aiming at a larger audience, writing in "digested" English, instead of harder to understand mathematical definitions, my text was "too vague"/"cryptic".