Sideways harddrives only in BTX?

When I first saw the BTX form factor, I thought, “Now there is a good idea, mounting the hard drives sideways.” (with the connector portion facing the side of the box instead of towards the back).

One problem I’ve always faced when working on PCs is that the hard drives are often difficult to add or remove, due to the cards blocking the access. Even on my Antec tower with removable hard drive bays, the drive sticks out far enough to run right into the PCI cards when I try to remove the bay.

Is this something you’ve ever seen on an ATX tower? I usually buy Antec or similar.