The game is announced for PS5 and Xbox Series exclusively.
It’s out of the question that it will be released on PS4/XBone, GTA VI will be a proper next gen (or current gen) game. And RStar would be making a fool out of themselves releasing a last gen game in 2025.
I’m guessing it won’t be released on PC for another year after the console release, but their GTA V PC Port has been optimized pretty well imho (even though they’ve pretty much abandoned it at this stage).