I like the single panel, because I use portable devices. I actually have a 15" laptop, and it is getting old, but will be replaced with a 13" device, when time comes. I tolerated Unity’s top panel, because Unity is unique, and also because it integrated with the open app. I like the ability put files/folders on the desktop, as that’s the place I work, and after finishing the job, I clean the place up, the result goes to where it should stay.
Some devs, it looks like, don’t have desks, work on the lap or balancing on a plate or something. I don’t need a menu all over the screen, but the screen as my desktop. If I needed a menu, I could get one from the Natty days, still working and all over the screen.
D2D is not updated to Gnome 3.34 yet. True, one of our people is there with D2D, but still it is a general extension, while UD is a less-option fork of it. The screeny is of Arch Linux with Gnome. D2D is the launcher. App indicator support is there. Desktop icons support is there. Files/folders can be dragged to and from the desktop. Most probably, this can be achieved with Fedora, OpenSuse and others. Nothing unique.
The sudden decision to move from Unity to Gnome was taken in 17.10, not much time to get the “Unity look” then. Most copy the Unity look, because it is unique. Manjaro Gnome comes with it. Even, Linux on DeX with Samsung comes with it. But, the real one can be had in LOD.
The Unity look is just a copy, and cannot take its place, so something unique has to be found, or Ubuntu would become one of the crowd.