To clarify: Custom note names (eg from note name files) are shown, auto-generated note names aren't. That's true not only on the keys (row headers) on the left, but also for note names shown on notes. And also with "Hide unused and unnamed note rows".
Although I never run into this as I use note name files with all my drums and drums is the only situation where I use the hide rows feature, I'd support a FR to have the auto-generated names shown on both, row headers and notes
.