I use Lightroom Classic (have for years) & Lightroom CC on Windows (although I don't use the Windows versions much anymore), have two Android Phones (Note 9 - Android 9, Pie & Pixel XL2 - Android 10, both non-rooted) and an iPad Pro with iPad OS.
I'm having an issue on just the Android devices that I wanted to bring up and it's regarding the auto-import feature. On both devices it can take hours for even a single photo to auto-import. Screenshots, Photos, etc. It will get there, but it can take anywhere from 15-30 minutes to hours. Shooting in in JPG + RAW or just JPG doesn't change the behavior. On the iPad, it's instaneous.
I have separate collections for each device, iPad to an iPad Collection, Note 9 to Note 9, etc.
For posterity, the settings on the Android devices are as follows:
Enable Auto-Add is enabled, with JPGs/PNGs & Raws selected on both devices, and each respective collection selected as the destination for auto-add
I've turned off Lens Profile Corrections, to no effect.
For syncing, Use Cellular Data is selected
The Pixel XL2 does not have an SD, so it's all local storage
The Note 9 is selected to use internal storage, but also tested on SD, no change