that we shouldn’t take dates on the show literally other than as an indication of the general order in which things happened
I absolutely am fine with this take now, especially. Ultimately, what we are talking about is the narrative importance of the events. If we want to have episodes where the characters go to "today" today must continue to exist within the narrative. If the narrative says that the world was noticeably different in 1996 - move it to 2036. If we're still going strong move it to 2056.
These changes don't make as much difference in the narrative that was being told to begin with.
This is a question worth asking. As others have pointed out there sort of seems to be clear that the rules are the rules and business rules trump all other rules. The Rules of Acquisition tend to be the Ferengi Alliance's highest law. It's both a religious law and a practical one and I think therein is where the problem lies. You can't make profit outside of the constrains of normal ethics because whatever makes profit is what is ethical to do.
This is why so many contradictory Rules exist in this system. War is good for business and peace is good for business, and neither of these are statements on what is "bad" for business. There's nothing here that says not to do anything and I think in this way Ferengi ethics largely comes down to there's no precept that says I shouldn't do this and I was able to exchange doing it for profit so ultimately it serves a higher purpose.
And since it seems like there is a fair amount of legalize extortion that happens in Ferengi while it might be technically illegal to do slavery, it might be more profitable to do it and therefore on the whole you can come out with an ethical conclusion that is "good" especially if you're some mid-level Ferengi in charge of making sure that slavery doesn't happen and you're able to take a little bit of a kickback.