Why do floppy disc drives have that center bevel?

I have a few old floppy disc drives laying around. They're missing front panels, so I figured I'd design and 3D-print some. I went for a simple design at first — just rectangular cut-outs for the disc and the button, and a cylinder for the LED. But when I attached this simple faceplate to one of my drives, I found that there are actually some specific reasons for why floppy drives always seemed to have bevels and/or cut-outs in their middles:

1. Without a bevel, fingers cannot easily push the disc deeply-enough for the drive to take it.
2. A cutaway allows viewing the disc, which lets you know there is a disc in there and what color the disc is (which might be enough to tell you what disc it is).
3. Bevelling only the center ensures that users only press in the center, which helps with disc alignment and even insertion.
4. Not bevelling the sides means they are able to function as angle limiters for disc insertion, which protects the disc and the drive from off-axis insertions. The more you know!

I also have an old USB floppy drive (TEAC FD-05PUB), and it also has less material in the center, though in the form of a circular cut-out with no bevel. This design is actually better than the old one when the drive is a peripheral, since it lets your fingers get maximally close to the actual drive. I do though think that the old design is nicer for drives located inside a PC, since there is case material above/below the façade of the FDD, and bevels are required to smoothly accomodate that.