Part of it is likely that she is a famous woman who is not known for being sexualized and is considered a public figure. No one wants to have the scientific standard be “I used pics of this girl I had a crush on” so I imagine famous people are good to pick from. I imagine Merkel also doesn’t have a lot of bikini pics AI can draw from (some amount of swimming pics are unfortunately always available for public figures for some reason) so you can be sure it’s generated them from nothing. If you used a famous model, there may be a possibility it is using pics of them to model their chest. If you’re testing what it does with random inputs, using Merkel is probably a good option.

As far as the output being what was requested, I think the issue can vary depending on your view of AI so I am just going to leave that part unanswered because if it’s a problem or not relies so much on your priors.