Reproduction steps:
1. Open the attached user's Unity project "DeltaTimeChecker.zip"
2. Build and install the application on a device
3. Open the application and observe the "Time.deltaTime" graph

Expected result: Time.deltaTime graph is stable (16ms)
Actual result: Time.deltaTime graph is not stable (between 0.01ms and 22.2ms)

Reproducible with: 2019.4.34f1, 2020.3.25f1, 2021.1.0a1
Not reproducible with: 2021.1.0a2, 2021.1.28f1, 2021.2.7f1, 2022.1.0b1

Reproduces with these devices:
VLNQA00319 - Google Pixel 4 (Pixel 4), OS: 10.0.0, CPU: Snapdragon 855 SM8150, GPU: Adreno 640
VLNQA00147 - Razer Phone (Cheryl), OS: 8.1.0, CPU: Snapdragon 835 MSM8998, GPU: Adreno 540
Huawei - (ELS-NX9), Android 10, CPU: NOT FOUND, GPU: Mali-G76
VLNQA00078, Motorola Nexus 6 (Nexus 6), Android 7.1.1, CPU: Snapdragon 805 APQ8084AB, GPU: Adreno (TM) 420

Not reproducible with these devices:
VLNQA00277 - Asus ROG Phone (ASUS_Z01QD), OS: 9.0.0, CPU: Snapdragon 845 SDM845, GPU: Adreno 630
VLNQA00404 - Galaxy Z Flip3 5G (SM-F711B), OS: 11, CPU: Snapdragon 888, GPU: Adreno 660
VLNQA00219 - Samsung Galaxy Note9 USA (SM-N960U), OS: 8.1.0, CPU: Snapdragon 845 SDM845, GPU: Adreno 630
VLNQA00109 - Xiaomi Mi Note Pro (MI NOTE Pro), OS: 7.0.0, CPU: Snapdragon 810 MSM8994, GPU: Adreno 430

Notes:
- Issue is reproduced on devices with a display refresh rate of 90Hz
- Issue is not reproduced on devices with a display refresh rate of 60Hz
- Does not reproduce with optimized frame pacing enabled, VSync wait enabled, targetFrameRate is set the refresh rate divided by an integer