What will happen if user has monitor with different aspect ratio than 16:9?
For example, I have 16:10 monitor with native resolution 1920x1200. How will game handle that? Display black bars top and bottom? For game itself it could be not a big deal - it could display game area bigger or smaller. But for cutscenes it is more critical, because layers are positioned in a way so no hard corners/edges are visible now.
I would buy new monitor, but only if they would release 4k display with 3840x2400 resolution (16:10). I like my vertical space. More lines of code visible, I find it very useful.
While custscenes are simple, the numbers Casey adjusts for placement, camera movement and speed are very tied to visible area on screen. Sure, while 16:10 is not that different from 16:9, it sill must be handled. It could be much worse on monitors with 5:4 (1280x1024) or other "ancient" resolutions :) But I guess that is not a priority for HH.