Well, I am a Turkish woman who grew up in Istanbul. I have visited several places in Europe, Asia, Skandinavia, and North America. Let me share my experiences about the stereotypes of people living abroad.
Firstly, most of the people who do not know anything about Turkish people think we do not interact with cross gender, we are dangerous because we are muslims (terrorism thing), we are extremely religious and all of us wear these scarf thing to hide our hair.
I was really surprised that here people still say that we are 'wild', interpret others' words as 'sexual invitation/harassment' and we do not interact with cross-gender. Probably people who types down these kind of 'experiences' visited Turkey in ancient times. And it is not etiquette as written on the main question but stereotypes.
You, as a tourist can talk to Turkish people with no hesitation and they will gladly help you find directions or any other issues. As most parts of the world, younger generations talk better English so communicating them will be better for you.
When I was abroad, a lot of problems I faced like people try to take advantage of you etc but I did not think 'the whole country' is jerk just because of 2 or 3 people. So maybe some of us here should reconsider before sharing their experiences and avoid generalization.
Let me finish my sharing with one of the best proverbs and hope all of these type of people who think Turkish people are 'wild' will get the point and enlight themselves a little bit :) "Stereotypes are devices for saving a biased person the trouble of learning."