I would like to rename my screens to something a little more understandable than "Displayport-0". Is there a way to do this?

Here is what it looks like now:

Not globally, every applications (in this case kwin) would have to provide its own mapping mechanism (what obviously is prone to confusion
Even if eg. "KDE" would provide a global string map, that would only cover applications explicitly opting into this (ie. not xrandr, gtk, plain Qt or every application which simply ignores that map ...)

The names btw. reflect the physical output port, what's pretty much unambigious nor variant