I’ve been thinking about gravitas. Your voice is developed and the more confronted your flaws and faults, the more authority starts to develop.
If you decide that big words makes one look more intelligent, you present yourself as striving to be relevant. Plain writing will let your readers know you are genuine. You don’t have to prove yourself if you are just honest.
There’s a comedian that appeared unsure of himself back in the 90s. Now he has decided to reference obscure subjects and be unpredictable in that manner. You can’t “figure him out.”
I like to think my authority more developed since I was in undergrad. It doesn’t mean I’m an “authority,” but just that I know myself more now.
Authority developed means territory staked out. I’ve just started.