Grand Turismo Sport is a major title releasing this fall on the PlayStation 4 and aims to be a graphically intensive racer for Sony’s platform. The game will not have a dynamic time nor dynamic weather cycle in the game.
Head developer Kazunori Yamauchi commented on the reasoning for this with the following statement: “We opted to not have the transitions in the race this time in order to raise the frame-rate and the quality of the image during the race. So the user will be able to set that before they enter the race. So you’ll still be able to have night races, morning, races at dawn, dusk, and so on.”
Considering GT6 suffered from frame rate issues on the PlayStation 3, the focus on stable performance is a noble goal to focus upon.
Source: https://www.gtplanet.net/gt-sport-will-not-feature-dynamic-time-or-weather/