If you weren't already aware, you can just drag the selected text slightly and it will retype it at the current prompt position, without dirtying your clipboard

If you weren't already aware, you can just drag the selected text slightly and it will retype it at the current prompt position, without dirtying your clipboard. QTerminal does the same on Linux, and likely other terminal emulators, too Or if you are copying it out of iTerm, replace "slightly" with "to the other terminal" :-)