PS4 has the best games but with the question phrased like that its hard not to argue that the PS5 is "better" since it can play those games and more, while the PS4 had no backwards compatability. So I'd be very suprised if the PS5 ends up having the exclusives, but you could still call it the best system. Except when it comes to fitting in a normally sized TV cabinet.
Try out my free game on Steam