Screencasts with downscaling
The new screenshot UI allows one to easily record a screencast of their monitor. However, with monitors resolutions growing larger, the resulting videos may weigh a lot and take a lot of processing power to encode. For many screen recording use-cases you don't need a full-resolution video: a half-resolution downscale (e.g. 1920×1080 instead of 4K—that is, half by each side, quarter in total pixel count) will still have sufficient quality, while taking up considerably less space and encoding power, perhaps allowing to bump the frame-rate to 60 FPS in more cases.
This could be expressed as an option in the UI, or maybe we should even just downscale to ≤1920×1080 by default (while resolution is > 1920×1080: reduce resolution to ½ by each side)—to me it seems that the use-cases that the current screenshot UI aims to cover do not mandate full resolution in all cases.