@Susie5 Yeah, it can be confusing sometimes. I often find little "gifts" from Airbnb that are unexpected and sometimes makes me scratch my head! But, to answer some of your points:
1. The 72 hours wait time refers to the Group Payments feature. When Group Payments (where multiple guests can pay their part of a reservation) are offered, Airbnb allows 72 hours for all of the guests in the group to pay. I already complained about this to Airbnb since 72 hours is a loooong time.
2. The no-photo issue is Airbnb's attempt to discourage discrimination. And, let's face it, many hosts decline based on what a guest looks like. For me, I don't care what a guest looks like so long as my conversations with them seem to indicate they are ok and / or they have good reviews and have Verified ID.
3. Actually there has been no change here. With Inquiries, all you need to do is respond. Airbnb encourages Pre-Approvals and Special Offers, but these are optional. Reservation Requests, on the other hand, are different in that Airbnb places an authorization hold on the guest's payment method to be sure there is enough credit available to pay should the host accept the reservation. Since authorization holds have a time limit, Airbnb asks hosts to Accept or Decline within 24 hours. See this link:
https://www.airbnb.com/help/article/28/what-do-i-do-after-i-receive-a-reservation-request
4. Yes, this is an odd change in policy. However, it is not uncommon for a guest to arrive and find out that the space is in horrendous shape, has bugs, is missing amenities promised in the listing, the host wasn't there to give them the key, etc. etc. My guess is that Airbnb wants to allow guests who face these situations to be able to leave a review about their experience. Remember that hosts can always leave a public reply to these reviews.
5. Well....all I can say is that Airbnb is always on the move as it has to compete with some big time competitors.
These are my two cents, err, 4 cents. Let's see what others have to say!