Here’s a pet peeve of mine: People using fancy words to prove their intellectual superiority (or lack thereof).
It’s funny as I find it usually much harder to express something in short, succinct sentences using everyday language than wrapping up your message in (mostly meaningless) complexity.
It is so much more powerful to express what you want to say in one singular, coherent, informative, insightful, spectacular sentence than using words which most of us need to look up in a dictionary.
Write everything, do everything, as well as it can be done.