On a title screen, a black screen is shown

I can press A to start game or X for accessibility on a title screen.
The trouble is that, when I start the game, the black screen is shown on a title screen, but a button to press to start a game or accessibility can be seen. Restarting the game didn’t help.
I’m playing this game on Xbox Series X.

Yep I got the same problem too. UI elements are visible like text and subtitles but the actual graphics for the game is completely black. Hopefully a fix will happen soon enough.

I’ve experienced the same black screen. A couple of restarts ended with the same results.
Next I Loaded Forza Motorsports 7 and was successful to play that game for a moment.
RESTARTED my Xbox Series X.
Reloaded Forza Horizon 4 and I was welcomed back by Anna.

Enjoying gameplay now.

I had the same issue with black screens when starting the game. I had the game previously installed on an external drive from my Xbox One X. I decided to uninstall the game and download it again on the new Series X. Seems to have solved all the issues. I had tried to just copy the previous install onto the internal drive of the Series X but that did not fix the issue.