Top bar can't be controlled without a mouse (on Wayland)
On X11, you can control the whole top bar and all its dialogs using only a keyboard. By pressing Ctrl+Alt+Tab, you can focus any element on the bar, and then using Enter/Space/Down show the dialog and navigate using arrows keys as usual. Alternatively, you can use Super+V to open the calendar+notification list and use Left/Right to switch between top bar elements and their dialogs.
This is all broken on Wayland. By pressing Ctrl+Alt+Tab, I can focus any element, but Enter/Space/Down has no effect, the dialogs never open. By pressing Super+V and Left/Right, I can switch between dialogs, but I can't enter those dialogs in any way. The only exception is the calendar+notification list, if you press Super+V and then directly Down, you can access that one dialog.
The outcome is that without a mouse, I'm unable to reach the application menu and especially the user menu. That means I'm unable to control the audio volume, network/wifi/vpn/bluetooth, etc. The user accessibility is severely affected on Wayland.
Edit: This is a race condition. On some boots, it works well (under Wayland), on other boots, it doesn't.
gnome-shell-3.34.1-1.fc31
Fedora 31