The announcement was made by High Voltage’s CEO Eric Nofsinger in a discussion with Nintendo World Report, who said that there might be a split-screen multiplayer option implemented in a potential sequel, but that would be an incredibly long wait time for fans.
However, you should not be upset on Sega or High Voltage: the report suggests that the developers intended to bring The Conduit with LAN multiplayer support, but Nintendo did not allow it. Why not is a big mystery. Maybe the Big N doesn’t like it when a third party game threatens to get bigger than any of the nonsense they might have planned for the future…