I've had some of these same concerns with personal identification of guests, and just talked to Airbnb on the phone about what is required.
PROFILE PICS: Others have reported that Airbnb requires all members to have at least one identifiable pic in their profile. That is NOT TRUE. They do require an identifiable pic be submitted to Airbnb in order for Airbnb to "Verify" their identity, but policy DOES NOT require members to post that pic or any pic of themselves on their profile. Airbnb says they retain that pic in their records, but they are not going to share it. Apparently, if a member posts only a pic of their cat on their profile, that is not a problem for Airbnb. If a host wants to require an identifiable pic of guests, they are more than welcome to make that a condition of acceptance in their HOUSE RULES.
FULL NAMES: A host might assume that once a booking is confirmed, they will be provided the guests full name by Airbnb. That is also NOT TRUE. In many cases, members do provide their first and last names on their profiles, but they are not required to. They can call themselves Joe S. or Joe Shmoe or whatever they want on their profiles, as long as Airbnb staff is satisfied THEY know their true name and identity. If a host wants to require the real first and last names of all guests be disclosed by the guest, they are welcome to make that a condition of acceptance in their HOUSE RULES. However, hosts never see the full "profile" names of guests until they have accepted a booking request. Only then does it become apparent that a full name is not being provided. If a host has made FULL NAMES a condition of acceptance in their HOUSE RULES, I'm told by Airbnb the host would be justified in cancelling the reservation WITHOUT PENALTY if the guest refuses to provide that information. And even if a guest provides a host their full name (by messaging, while still not showing it on their profile), the host has no way of verifying that the guest is providing their real full names, apart from asking to see a photo ID when the guest arrives.
INACCURATE PROFILE IDENTITY INFORMATION IS ALLOWED: Airbnb knows who verified members are, since they have the benefit of matching their face pics with their photo IDs. But to protect the guest's personal information, Airbnb will not directly share either of those things with other members. Airbnb will provide a member a "Verified" status, even if that person decides to post a picture of their cat and call themselves "Tom Cat" on their profile. Airbnb places full responsibility on members to verify that pics and names shown in profiles are actually the pics and names of the member requesting a booking. To me, it's like Airbnb saying to hosts, "We know who this person is, but we can't tell you because of privacy issues. If something goes wrong in your home, and the guest is responsible, we will make sure the guest takes responsibility. We will do all of this without revealing the guest's true identity."