Thank you Sarah and Brian for your thoughts and support!
I know this is a conversation platform for hosts, but once (regarding not showing profile pictures before after booking) someone from Airbnb did respond. I have, of course, also filled out a feedback form. And will probably write it to support as well by opening a new case.
I will continue declining guests whom I feel uncomfortable with already on the request stage. And since one has to write a few words to the guest why the decline, I started writing that I am not used to this kind of communication, period, next guest. And I write the same in the Airbnb reply field.
So with time maybe these small efforts by ourselves may give a result.
Btw, I am also very focused on profile pictures that actually show a clear face as many users don't have that, and Airbnb does not require this (strangely enough, as they speak highly of security and transparency!).
I obviously don't have Instant booking enabled, but ask every guest to answer a few questions when making a request. I don't know how much 'business' I lose by this, but for me, as indicated, Airbnb is not a business first of all, but a shared economy initiative to pay some of one's rent and to help other people travel. That hotels and other pure business accommodations can now be on Airbnb, is outrageous as it does not fulfil this goal.
Have a lovely Sunday, I just got an extremely friendly request that I need to respond to – it was worth waiting for 🙂