Lower-case -y stresses the drives.  It spins them back up just to spin them down
again.  (I tested it, you should be able as well.)  That is the worst stress for
a drive.  At shutdown drives are re-awakened (spun up) and immediately shut down
(spin down).  You hear the procedure even without a screen.

Please report kernel flaws upstream.  This may be one.  Reports have more
credibility from you than me.

Since IDE drives are already dismounted and spun down, there is no reason for
system shutdown to re-activate them.  It is unnecessary stress on the drives and
time-consuming:  a real bug.

Right now capital -Y is safer than lowercase -y because -Y does not re-activate
drives.  The manual workaround is that when "interrupt lost" message scrolls
along, do a manual power-off.  Not ideal, but better for the drives than -y.