Think about this.
Paradox bought Whitewolf for all their RPG content, they are maintaining EU4, CK2, Stellaris, and HOI4 and making DLCs for those, they probably are working on an EU5, and Victoria is among their least popular games.
They have a lot of stuff on their plate at this point and they just opened an IPO so are going to be beholden to whims of shareholders.
IMO the chance of Victoria 3 is low. I would hope for Victoria type content to maybe be in EU5 with HOI4 having a WW1 expansion but i'm thinking it's going the way of Rome at this point. That recent Vic 2 patch was a side project of people working for them, that is how little they care about Victoria. It's an abandoned franchise.