The current solution would be to review suggested edits and make sure those ones get denied, and then hope to God that the user doesn't get enough reputation to make them without approval.
We should probably have a nudge for users using backticks for the first time, especially in an edit, reminding them that they are for code formatting and not highlighting important terms.
While this might seem like enforcing our style guide pointlessly with a heavy hand, I'd like to remind everyone just why we don't like it when people
code highlight almost every
noun in a
A big part of the draw of this network is that our content is very legible. It follows a rigid Q&A format so you can immediately read whether the question applies to your case and then right below it the best answer - and all this without sifting through inline discussion, signature blocks, and taglines. This is why comments go in the comment box, and taglines are prohibited in favour of user boxes.
Similarly, the text flows nicely without awkward formatting. Code is code and is in fixed font and highlighted for contiguity; text is text and is formatted in a nice legible variable-spaced font and is not highlighted since it is expected to be concise. If highlighting is really necessary, there are bold asterisks
Messy formatting makes for text that is difficult to read and bad-looking, which makes readers subconsciously trust the text less. Far from clarifying things, needless backticks do the opposite of what they are intended for.
Simply denying the edits without reason doesn't provide enough feedback to make a user stop. Therefore, we need a nudge. Someone should write up a feature-request for one if they can think of a useful way.