I’ll grant you it’s not obvious, but it’s quite easy once you know (as with most things in GUIs): just drag it. You can drag a file/folder from Finder to Terminal or a text editor and it’ll populate the full path.

You can even drag a folder from a Finder window to a save prompt or web browser upload prompt and it’ll relocate you to that directory in the prompt.

The rich drag and drop functionality is one of my favorite features of macOS.