There's nothing wrong with tailoring your writing towards a segment of the public... assuming you can do it. Some writers are quite good at it, but not all.
But targeting a stereotypical group is always problematic and imprecise; not everyone in such a group is actually going to know the same words and idioms, or desire the exact same thing from a book. The most you can do is assume a "largest common denominator" and write to them, thereby risking the alienation of everyone else. If your LCD is large enough, that may be fine; otherwise, it's a wasted effort.
Generally speaking, you rarely go wrong in overestimating your audience (by at least a little)... most of them can learn. I just write and assume my target audience can handle my writing style well enough to enjoy the story. I avoid going overboard in jargon and wordy descriptions, and it seems to work.