If you hit the escape key in the Import dialog, the dialog is exited and all organization is lost. The expected behavior would be to exit Loupe View and return to Grid View (staying within the Import function) as happens in the Library Module. I have muscle memory for this behavior and I keep destroying my organizational work within the Import dialog--(ie: checkmark selections for "Include in import")
Either make the behavior consistent between the modes, or add a warning that "All selections will be lost, exit anyway?"
I never realized Esc switches Loupe to Grid until you mentioned it and I tried it. My muscle memory is to toggle between E (shorcut for View > Loupe) and G (shortcut for View > Grid). Because those shortcuts are consistent with how other modules work.
After being made aware of that, this is not the answer you want, but…I think it’s odd that Esc does that in Library. To me, that is the inconsistent behavior, because in no other module does Esc go to Grid. So my angle on this feature request is — and again, I know it isn’t what you want so go ahead and disagree — is that the Esc behavior in the Library module is wrong, because it is out of step with every other module, and out of step with what Esc does in most Mac & Windows software. That Esc switches Loupe to Grid in Library is in my view the bug that needs to be fixed; that function of Esc should be disabled since Lightroom Classic has another keyboard shortcut that does the same thing more consistently with the other modules.
Now, what Esc does in Import is, actually, quite consistent with other Mac/Windows software, because Esc is widely used as a shortcut to click the Cancel button, often interchangeable with the Command-. (period) shortcut. The Cancel button exits Import without saving changes, and the Esc key is a common shortcut for Cancel, therefore Esc in the Import dialog box is functioning there as it does in most other software.
I do use keyboard shortcuts to switch betwen Loupe and Grid in the Import dialog box, but the dialog box doesn’t accidentally close because I press E and G, consistent with the Library module.
I realize what I’m suggesting would require retraining muscle memory, but consider that it would be more generally productive to retrain in favor of how Esc works almost everywhere else.