Definitely not new. Almost exactly 15% based on that screen cap, which is about average. Airbnb says the average is 14.2% but they are not very transparent about the range.
https://www.airbnb.com/help/article/1857/what-are-airbnb-service-fees
You can find info online indicating the guest service fee ranges anywhere from 8% up to 20% depending on region and the total price of the reservation. The guest service fee is where Airbnb actually makes their revenue. The 3% host service fee is barely enough to cover the transaction service charges for guest payments and host payouts.