Maxwell's Demon

Why does everyone seem to insist that Maxwell's demon is an ideal and arbitrarily small machine? Wouldn't a passive element be much more natural to consider?
Further, why is it nowadays considered, or likened to, a physical existence, when it is literally a demon? In control of a wall with no physical qualities beyond reflecting particles? Wasn't the "agent" described as a demon because it did not physically exist in the speculation.

Couldn't, and shouldn't, the opening and closing of a spooky wall be transformed into a series of diffraction elements, lenses if you will, that redirect a particle to a nearly 90° angle, if it does not approach at such, followed by a nonabsolute barrier, a potential energy slope if you will, that can only be surmounted by a particle of sufficient speed.
A failed particle would reverse motion only perpendicular to the slope, and is redirected by the "lenses" to a new trajectory, as if it was somehow delayed from ricocheting.
Without the delay, the motion of the particle against the slope would be wider, and the barrier would as such lose efficiency to the lateral velocities of the particle.

Like this, the thought experiment is transformed from superstition into science fiction, and the only spooky things that remain are the two passive elements properties as perfect insulators. 
I'm fairly sure diffraction does not qualify as spooky.

It was a thought experiment of how to violate entropy, a simplification of the process, it should not be depicted in a manner that straw-mans any notion defying the law.