In iOS 12 beta 11, which was released yesterday for developers and public beta testers, it is finally possible to delete all notifications with one gesture, even on models without support 3D Touch.
In previous beta releases, this required pressing the 'x' icon to make the 'Delete All' button appear. In iOS 12 beta 11, the 'x' icon can be simply held down to reveal the same button.
It's very easy and convenient. This method will not work for iPhone with 3D Touch, but you can temporarily disable 3D Touch in Settings to activate this gesture.
Interestingly, many functions 3D Touch were added to models without technology support. These include the ability to turn the keyboard into a trackpad, the ability to scan documents from the home screen, and a QR code through the Camera.
Perhaps this means the technology 3D Touch did not live up to the company's expectations. Rumor has it that Apple will even ditch it entirely by 2019.
Other changes iOS 12 beta 11 include the ability to view all applications of a particular developer in App Store, improvements to the Maps application, etc.