Regardless of whether or not it is muttar, no lady with any sense of tznius/self-respect will deliberately put herself in such a situation if it is avoidable
Maybe, maybe not. Maybe she doesn’t expect her neighbor to look out the window at her swimming pool with his binoculars. She’s not changing what she wants to and can do al pi Halacha just because of some peeping tom.
Let me ask the question this way: When a girl walks in front of a Frum boy, is she doing something similar to what the lady in your hypothetical case is doing if she KNOWS that there are men who will be deliberately watching her?
No, she is doing something worse. By acting specifically in a manner that shows herself off IN PUBLIC, which even when the “ervas” are fully covered, she is Over Da’as Yehudis. If “she KNOWS that there are men who will be deliberately watching her” (AKA Histaklus) doing this act, because of that action, that would be “Vered” (IMHO).
If a woman is so beautiful that she can’t walk normally in public Tzniusly without people staring at her, I don’t believe that is her problem. The guys are Mechuyav not to look.
Does that answer the question?