I think this is not related to Oreo > Pie transition (occurred for me long ago) - mine got broken after recent November Pie sec patch.
For the config P2XL (latest sec patch, 9.0) + Lexus CT 200h (2014) + Spotify (latest) , I've tried different actions such as: re-pairing, changing AVCRP version and repairing etc.
I can't remember for sure my entire flow to work around the issue, but it was like:
- Remove the phone from car's head unit
- Forget the car in your phone
- Wipe user data for the Bluetooth system app
- Set AVCRP to 1.3 (from Developers menu), reboot
- Pair the devices
- Play some music via G Music (it was showing meta datam while Spotify wasn't)
- Disable Google Music app (not sure if it was necessary)
- Repeat removals/unpairing and pair again; run Spotify
- PROFIT (at least for me)

Please be advised that the steps above likely will require re-pairing (i.e. reset) for your Wear device (if you have any ) .

I guess some of the steps are totally not necessary : ) But the solution is fine a temporary one - the metadata works fine for ~2 days. Fingers crossed. Waiting for solid software fix from Google. ( follow https://issuetracker.google.com/issues/112448122 )

 

I have this same issue which forces me to use Bluetooth all the time. Did you ever figure out how to fix this?

 

My Spotify metadata finally started refreshing song titles earlier this month.
Anybody else have success?
Seems like an update occurred on Android or Spotify.