It makes no sense because the concept of putting on a star-spangled one piece bikini with boots to alleviate fears of an outsider is silly. She already has Trevor, a pilot/soldier, to vouch for her. Like Superman, her heroic deeds would have put much of the fear aside. Especially considering she's an Ambassador of Peace. The only real reason to have her do something like that is because it's the outfit she was given originally by a kinky, misogynistic creep. That's all. It's a continuation of making up excuses to have her keep her original outfit to shy away from that fact.
To be fair, the Amazons were never modest with their clothing; both in DC fiction and Greek mythology. And by extension, Shakespeare's female characters were the same:
Back on Themysicra, they simply wore togas (or some variation of it), with no undergarments underneath.
Diana, and her people, have grown-up with the mindset of wearing loose clothing, so when her outfit was crafted by her mother, it's makes sense that the contents of her attire was in the same vein of how the Amazons dressed.
Now, I'm not saying her outfit WASN'T an excuse for the creator to perv out, however, going by how Amazon's have always dressed and the inspiration of Greek lore, it makes sense that her Wonder Woman costume is of little clothing, and resembles the revealing female warrior "armor" of Greek Mythology.
Add American colors to said Amazonian attire, modernize it a bit, and you more or less have that.
They even poke fun at her mindset on Justice League. She's so used to loose clothing that it doesn't bother her.
Don't Tell Wonder Woman What To Wear