Yes. I imagine solving Maxwell's equations for this geometrical arrangement of neodymium magnets and cable would clarify all too clearly why they have "lackluster USB 2.0 speeds".
Which devices are still susceptible to magnetic fields? besides HDD
Quite a while (see my other post).
But what about corrupting data?
If you're still using devices relying on magnets; it's time for an upgrade.
I mean when you move the cable. The magnet will induce current on the data lines.