Below are two screenshots. In the example, I wanted to link to a space directly which happens to have the same name as a page.
First, the old editor and linking. It was easy, I typed [ and got a useful dialog. even if there was ambiguity, I could hover over the link and see the URL in my browser status bar.

Second, the new experience. I don't even know what to say. On top of what you see below, I cannot hover and see the URL in the status bar. I mean, just, wtf?
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And why did we change the shortcut? So now the system is fragmented. I can still type // to get a date or @ to tag someone, but now I have to use CTRL+K to link?
In summary, old: good, new: bad.