[Stuart]

Just me that can't unsee the dodgy edging here?

I suspect it's because you're only seeing the inner edge on the final part of the sloped area.  If you could see the whole slope from a different angle you would see a similar raised 'lip' slowly getting narrower.

The lightbox under the desk platform has a similar gradient, but you can see all of it.  The outermost edge of the platform is the same height all the way round. It's only the inner wooden part which is sloping.

There is no 'dodgy edge'.