There are several areas of Rise of the Tomb Raider with framerate drops, particularly anything with snow deformation. It affects all Xbox One consoles, no one got a magical one that lacks the issue. Ignorance is bliss I guess.
Putting it on the PS4 might not have made any difference though, Crystal Dynamic were targeting high "cost" features like SSAO and AF. The PS4 is more powerful than an Xbox One but it probably would've hit similar issues.