Reproduction steps:
1. Open the attached user's Project "video-player-test.zip"
2. In the Project window under "Assets/Scenes" open "SampleScene.unity"
3. In the Hierarchy window there is a "RawImage" GameObject under the "Canvas" GameObject with the Video Player Component and "Video Test.cs" Script
4. Build for Android

Expected result: the video is played
Actual result: the video is not played

Reproduces on: 2018.4.28f1, 2019.4.13f1, 2020.1.10f1, 2020.2.0b7, 2021.1.0a3

Reproducible with these devices(Vulkan, OpenGLES3 and OpenGLES2:
N/A, Samsung Galaxy S9 (SM-G960F), Android 8.0.0, CPU: Exynos 9 Series 9810, GPU: Mali-G72
VLNQA00339, Lge LG V50 ThinQ 5G (LM-V500N), Android 10, CPU: Snapdragon 855 SM8150, GPU: Adreno (TM) 640
VLNQA00316, Samsung Galaxy Note10 (SM-N970F), Android 9, CPU: Exynos 9 Series 9825, GPU: Mali-G76
VLNQA00024, Xiaomi Mi 5 (MI 5), Android 7.0, CPU: Snapdragon 820 MSM8996, GPU: Adreno (TM) 530

Not Reproducible with:
iPhone 6S (iOS 13.3.1)

Notes:
-The issue only occurs when setting the Video Player Source URL through the "Test Video.cs" Script, if the Script is disabled and the URL set manually then the issue does not reproduce on Android
-Issue occurs only when Building for Android, Editor works as expected