I'm really hoping this means it's not a reboot, but a continuation and after Egon died (the movie will have a huge meta memorial) the lab where he did his science stuff got all his equipment and some bad guy there released the ghosts (had been contained for 20+ years) and Egon's daughter is the only one that continued with the science and understanding, Ray is too old so he can't do much but Egon's daughter gets her friends together and they go bustin'.
..or something.
..or something.