In RIME we had a material collection which contained the “time of day” (brightness) and the “day color” (orange in the morning/evening, blueish over the day) which we used to tint our materials. We often used unlit/emissive materials to get a stylized feel to the VFX and needed to colorize our effects depending on if it’s day/night.
For that such materials collections where amazing! You don’t want to write code/blueprint which changes every single material one ofter another. The code just changed the daytime/color and everything was adjusted.
If you want more detail: https://youtu.be/fwKQyDZ4ark?t=1268