Could just be me, but I understood that post to mean "Don't copy over actions on to jobs simply for the purposes of giving that job a competitive equivalent." Which is very different from "Don't create an action that in any way resembles another action already in the game."

The former actually makes sense. Let's use the change to Shake it off in 4.2 as an example. The problem wasn't that Divine Veil was already in the game. If anything, I feel like Veil's design could be further improved on by taking notes from Shake it off, just like Shield Swipe was improved on by taking notes from HW Reprisal. If something works well from a design perspective, it makes sense to take note of it. The problem was that players went to the devs with Shake it off and said "We don't like this action, where is our Divine Veil equivalent?" The correct response to that is: "Why do you always need to have an equivalent?" The problem wasn't the end point. The problem was in the process.

The latter, of course, is so absurd that it's not even worth expending the effort of posting counter-examples. I think you actually made it harder for yourself by forcing yourself to prove that Reprisal was identical to Haymaker. The reason you had to omit mentioning Shield Swipe (which is the more obvious analogue than the obscure Haymaker) was because Swipe ended up being changed to become closer to Reprisal. The whole thing was an unnecessary stretch.

What was the easier response? Well, Reprisal, Delirium, and Scourge are all Actions. You press a button and something happens. Didn't other jobs have those first?