This makes zero sense to me. It's all just cloth. The person in a g-string & harness is, literally, less exposed. You're conflating the context of "being exposed" and "adds to the exposure". Those two phrases mean different things. The first is referencing how much skin is visible while the second is referring to how noticable and attention-grabbing the individual is. You would be arguing an entirely irrelevant point to what was being discussed in your own hypothetical

Clothing being "suggestive" is entirely a subjective concept. What is "suggestive" to you might just be something the other person finds comfortable. It is also the same general logic behind "look at what she is wearing, she was asking for it" and I find that really problematic.

The underwear example is also just dumb to me. It's just cloth. It isn't "meant to not be seen", it's just there to avoid regular clothes chafing sensitive areas of the body. It being seen is irrelevant and simply a coincidence of being worn under other articles of clothing. There are no inherent, underlying implications except for what you put on them through your own bias.

This just reaffirms for me that people like to add arbitrary, subjective aspects to things and then try to assert these as intrinsic facts instead of personal biases.