The Maxwell conjecture is a toy problem. The existence or nonexistence of a bound on the number of equilibrium points in an electrostatic arrangement of point charges doesn’t change much. I say that as an EE but not a specialist in electromagnetism.

> what does that mean for Maxwell equations?

Nothing. They're still just as valid as they were before.

> For electromagnetism?

In practical terms, nothing significant. It's not going to change how anyone builds devices that use electromagnetism.