That looks like repeated damage from sloppy top-end reassembly with the link misaligned, and my guess would be that the base of the guide rod is probably slightly undersized (or was at one point

) allowing extra movement / tolerance for misalignment, at least that’s typically been the cause of similar damage I’ve seen.
When attempting to re-assemble a top end with a FLGR as a complete unit, if the link is to the rear (which it will often naturally want to do if you don’t hold the spring / FLGR in place, it can get slightly misaligned with the frame / spring channel:
These photographs are obviously exaggerated / taken under artificial conditions (not under spring tension in the second photograph because I don’t want matching wear on my own $hit

), but if the FLGR is misaligned, you’ve got two choices really… actually fix the problem and re-align the FLGR, or just manhandle it and repeatedly slam the slide back and forth until it jams itself into the correct position and the slide finally slides home.
Because most recoil guide rods are typically softer than the slide and frame, your guide rod’s base can start to get pretty mangled without much wear actually showing on the slide or frame—the guide rod will just continue to take the brunt of the damage (unintentionally peening it until it fits properly within the channel

).
This looks like the work of someone who regularly removed and reassembled the top end without worrying too much about the link location and would just slide the top end on, slam it back and forth a couple of times until the guide rod found the right position and slid back and this was probably their normal reassembly process—probably didn’t even have to do it too hard, probably just one or two slams each time over a period of years, and over time the softer guide rod getting pinched between the slide and frame would get pretty ugly, if it has been a one-time thing you’d probably see more evidence on the slide and frame, which is why I say this was probably “normal” for the guy.
Chances are they rarely actually removed the guide rod / took the slide fully down, so the damage would be much less noticeable when the complete top end was together, especially if he wasn’t taking much time to look at the link / worry about the link position.
~Augee