The Mario Kart Tour game assumes a refresh rate of 60Hz.
The game does not support features that increase a screen's refresh rate.
For example, the smooth display feature on a Pixel device, the high-speed display feature on an Aquos device, or the motion smoothness feature on a Galaxy device.
If you notice an issue during a race regarding your on-screen display or game functionality, the issue may be resolved if you disable the device features mentioned above or if you set the refresh rate to 60Hz.