@Ben551 Thanks. I read it. I don't think hosts object to not being able to see a profile photo of the guest before they are accepted because we think we can tell that this is a nice person or is going to be a good guest. Of course just seeing a photo of someone can't tell you that (some very horrendous sociopaths are quite good-looking and look friendly and non-threatening, that's how they are able to manage to get people to trust them).
The point of being able to see a profile photo is that we are allowing perfect strangers into our homes, which means we are accepting them in good faith and opening ourselves up without a lot to go on. If a guest is too "private" to want to post a photo of themselves, then they are not welcome to stay in my "private" home. They can see a profile photo of the host before they book- it needs to be a 2-way street.
Also, seeing a profile photo ensures that when guests arrive, that hosts can see that at least one of the guests is the person who booked.