The Lazarus IDE does do it on Linux across the system and, to my surprise on windows
I don't see that behavior in Lazarus on Ubuntu (gtk2) or Windows (win32) or Mac (carbon). (All run from Mac, so using trackpad.)
You're saying that just selecting text, say in the code editor, copies it to somewhere that can be pasted via a 3-fingered salute (not Microsoft's Ctrl+Alt+Del)?
I do note that the Paste command in the Laz Edit menu always seems to be enabled, even if there's nothing on the clipboard. I don't see that oddity anywhere else (Word, Pages, BBEdit).
Note that Ctrl+X, Ctrl+C, Ctrl+V and the others were popularized by Windows. These are the Windows equivalents of the Mac's Cmd commands, which MS copied (and good that they did so that these keystrokes became a standard). I've always thought that Apple's thinking was pretty clever: X like a scissors, V like an insertion point, and C, well, because copy started with C. Cmd+Z being right next to X, C, V then became undo. So simple, so intuitive.