The only thing wrong is it's still an Xbox One in regards to game installs. They really need to catch up. Just put Rise of the Tomb Raider in for both it and the Pro and the latter was done within 5 minutes (updates and all).
I'm like you. Got RottR on both PS4 and Xbox One! I'd do the experiment myself but I'm ready to play!
Luckily, I already updated all of my Enhanced games on my Xbox One S. When my X arrives, all I should have to do is update the console and plug in my HDD.