The short answer is that some probably will, and some probably won't. Much like games on the PS4, some titles will opt for a higher framerate, while others will favour better graphics. Some will settle for 30 frames-per-second, and others will aim for 60 frames-per-second. It obviously all depends on the game.
As mentioned, however, the PS5's increased power could, in theory, make 60 frames-per-second easier to attain. With that in mind, it's possible that we could see more games aim for 60fps rather than 30fps. In fact, some games will even target 120 frames-per-second, and you can find a full list through here: All PS5 Games Running at 120 Frames-Per-Second.