What would be nice for is to be able to not only open the app on my PC or Mac, but being able to copy text (like a sentence) *from* the app *to* the desktop. Is that possible in some way with this scrcpy? A simple Ctrl+C and Ctrl+V method, so to say.
Copy between Apple devices is a default part of iOS/MacOS already. Devices must be on the same network for it to work though. I frequently use copy/paste between my Mac and iPad (into Pleco) and vice-versa. This is not something that works on PC nor Android though.
On your Mac, use Universal Clipboard to copy text, a file, an image or photo or a video, and then paste it on a nearby Mac or iOS device.