Extremely well done (at least for desktop). Many seem to dislike that it's scroll-controlled, but tbh I would've given up immediately if it were free navigation—I didn't feel like wandering around looking for things, just wanted to observe the sights. And since the core structure is a sequential list of sights, the scroll interface is a nice way of keeping that linear structure in place while automatically choosing nice camera positions along the transitions.
There are many other small interaction cues that are expertly done, bringing in various optional jump-off points (e.g. viewing the same scene present day) without breaking continuity to explicitly teach anything. Another example: highlighting text on in-scene plaques as they're read (with high quality voice-acting). This is a well thought through experience.
Because it gives you easy access to continuous motion. I found myself constantly making slight adjustments to move a little back or forward to get better looks at specific things. It’s the same kind of freedom you get from mouse freelook in an fps but simpler to control because it’s collapsed to 1d.
There are many other small interaction cues that are expertly done, bringing in various optional jump-off points (e.g. viewing the same scene present day) without breaking continuity to explicitly teach anything. Another example: highlighting text on in-scene plaques as they're read (with high quality voice-acting). This is a well thought through experience.