I think how it's received is down to the confidence of the woman, too.
Some are embarrassed because they are shy or, if they are insecure about how they look, they think the whistler is taking the p***.
Personally it doesn't bother me - if there are "comments" instead of or as well, I can give as good as I get. ("Show us yer t**s, love." "Only if you show me your b***s first."
As others have said, these days I'm pleased if I'm worth whistling at!