I Inserted a Flat Pattern view into my drawing from the View Palette, annotated it, and tried to rename that view to Flat Pattern.

Error: "The name already exists, or is invalid. Names cannot be empty, or contain the following character ( '@' )."

So I named it +Flat Pattern+ instead, which works. Other views, in case you're wondering, are currently named Drawing View2, Drawing View3, Drawing View4, and Drawing View5.

Is this normal behavior, or does it indicate something wrong?

The only reason I name views is for linked view labeling and for PDF bookmarks automatically created.

Ref 2018 SP2 install.