Electrons do not carry the signal. Electrons barely move in a conductor in the presence of an electric field potential. The signal is a transverse electromagnetic wave that propogates down the cable.And why is it OK for cables to rest on lifters but not on rack or floor surfaces? How do the electrons behave differently in one scenario vs the other?
Cable elevators (can) do two things: 1) by lifting them off the floor, they prevent imparting vibration from the floor into the dielectric of the cable. This vibration imparts triboeletric noise in the dielectric, which has an effect on the signal, and thus has an audible impact on audio quality. 2) depending on their design, they can mitigate the static e-field that is created when a cable is lifted off the floor. This e-field is measurable with a e-field meter. This e-field also has an audible impact because once again, you guessed it, they act as a NOISE FACTOR on the signal EM wave propogating down the cable. One therefore, ideally needs an elevator that dissipates this static e-field that occurs when lifing a cable off the floor. An example are the Shunyata DF-SS cable elevators, which have a static electricity dissipating material in them, their Zr-Ca material, that dissipates the static e-field. This also provides an audible improvement in audio quality compared to a "standard" cable elevator. I used to have some 3-D printed cable elevators, and when I got the DF-SS, they made quite a noticeable improvement in audio quality over a "standard" cable elevator. Based on their design, it looks like the Nordost cable elevators may dissipate the static field as well...this is a hypothesis, though.