This is interesting. Here's a clip of a report that is sitting on one of our dashboards. It says "Showing all 13 projects" and there's no carot because that's all the lines for that report.
Other reports that we have on the dashboard set to show just 15 objects, but have more, show 15 of however many objects total there are
I wonder if this is a New Experience/Classic difference. We're using the New Experience, are you still in Classic??