Reprisal was removed from DRK kit and spread around, which is fine honestly. It's a tool everyone has equal access to, which means it isn't exclusive and doesn't really have much of an effect on Balance. Before the ShiO rework DRK and WAR were identical in having no party miitgation aside from reprisal.
You need glasses man, the only 'buff' in this is removing incoming crits. PLD and DRK have their damage completely unchanged, WAR is the only job that had anything happen to its damage output, unless you include limit gain from shake but even still I don't think that's what you're talking about. PLD loses Veil, WAR loses Shake (two changes that mean nothing to most people in most content performing at most levels), that's it.
This may shock you because I've posted in other threads over the past while that I think damage debuffs should be gone for well over a year, but inasmuch as it has to do with slashing and tanks and comp I don't mind it as much. While applying the debuffs isn't exactly an active decision like other damage effects there is a decision at the time of making your comp to choose one job over another. If WAR does less sustained damage (and to be clear, the nerf I wrote is paltry to the nerf I calculated and thought of using) then in compositions with a NIN or SAM the job is just less appealing. This should be the case when it comes to redundancy in damaging effects, it just doesn't matter right now because damage buffs are too limited in variety and availability for them to be of a concern to the group. If Debuffs were more varied then slashing and redundancy make sense, right now they don't as a matter of design and that's fine.
Right now you have 4 options: Bring slashing on a DPS (preferably NIN), bring it on a tank (so WAR), not bring it at all (which is bad), or bring two slashing by accident, which has no drawback because there is no opportunity cost. If you want to avoid the third scenario, which is the case if you have no WAR or no SAM/NIN, you gotta make concessions to get the buff. I think that's more or less fine, it might be frustrating but that's just part of putting a group together; you have objectives and you can attain them in a limited number of ways. Slashing is just one point where the decision is made at the time of comp, not when you're fighting a boss.
For the changes I listed, slashing gives you the benefit of an option in your melee spots if you bring it, it's something that's useful.
DRK is fine, I don't really wanna change DRK. DRK was reasonably positioned in Deltascape before they made unga bunga WAR and people migrated away from it and into the open hands of the WAR buzz saws. It's better now, but people doggedly follow their own tails around the raid shielding thing which makes DRK preceptually worse but practically identical to the other jobs. The WAR nerf is like 90 DPS, it'd only barely put it behind DRK and PLD on perfect uptime, let alone adds or downtime. This sort of change would be more or less immaterial.
The nerf to WAR is about statement; without shields and with comparable DPS WAR and DRK would be more or less identical in damage but with different mitigation, different damage delivery, and different aesthetics.