Real bummer if true.
I'll be calling to see if I can pause my membership or something if this comes to pass. If I wanted to only see lights in a theme park I'd go to Worlds of Fun. The near full ride collection being open is Six Flags' signature winter trait.
I notice on the SFSTL site that HITP is being called "Holiday in the Park Lights." And it no longer lists the rides that will be open during it. Things could change between now and then, but maybe the number of open rides will be scaled back a lot this year during it?