Honestly I hate saying it, but just not loving android.
I have amazing WiFi speeds, ive tried using mobile data - playing any photos within the gallery app that are on the one drive take FOREVER to play to the point I end up downloading them to watch without glitches.
Why does it do this? I dare to ask, but does iPhone cloud do this as well?
OneDrive has limited speeds, but so does iCloud. You can have the fastest internet in the world, and it can take time. OneDrive can throttle uploads and downloads to manage bandwidth usage and prevent network congestion
Few troubleshooting *settings- general- reset- network. Restart phone and reconnect to wifi.
Once connected go to settings- connections- Wi-Fi- gear icon next to your network- "view more" change DNS 1 to 1.1.1.1 and DNS 2 to 1.0.0.1 *this will connect to cloudflare and may help with speeds. Restart phone.
*the resolution is under "Video info" and on that image its 1440p. To download a 1440p (2K) video, you'll need an internet speed of at least 10-16 Mbps.