At this point, unless they release another "classic game bundle" style item like the Neo-Geo X, I'd say the chances are completely nil. If they did the former again, it would require a licensing agreement with a different company to manufacture them, as they don't have the capital or wherewithall to handle the hardware internally. Since the Neo-Geo X was a total fiasco, I don't think they're keen to try again.
Consider that they're making good money on ports of their games to the Switch, which basically is a Neo Geo X done right both in concept and execution (that and that whole "play awesome Nintendo games on it and we don't have to be involved with the hardware at all" aspect).
As for completely new, modern hardware, good luck competing with the Switch, PS4, XBone, and PCs in a market that requires you to be a super mega company to manufacture and support console hardware. They'd also need a lot of third party support, and something that would make them stand out from the competition. So yeah, totally not happening. SNK is software only from now on, full stop.