You can use uuids, labels or device names. Nothing has changed
The defaults the installer uses have changed, and it makes no sense for
the installer to ask new users questions like
Use UUID, LABEL or device name ?"
Because the answer in 99.99% cases is "uh ??"
In which case (and only then) the installer can choose for them, but let
there be choice with sensible (and visible) defaults for the others.
Because if I'm a new user and I want to change, say, from UUID to labels
(post-installation) I may not know how to do that. You don't suppose new
users would know better after than before, do you?