The problem with the implementation of the two-tiered difficulty is which one did they intend to be for the general population who has a static, but not nessescarly considered hardcore? "Normal" mode is so immeansely undertuned that it beyond any doubt, the developers intended for this to be clearable through duty finder without any prior setup or thought in regards to who you're playing with. Savage on the other hand, is debatable the worse incarnation of FFXIV's raid with it being tuned so hard for the majority static and collapsing underneath itself with the break down of statics and transfers to super-servers like greg or Balmung.
If Savage was intended to be hard, nerfing it defeats the entire premise of it. On the other hand, normal doesn't need rto be nerfed because they intended for everyone to clear it. So people are left head banging themselves on content that's designed for the top 3-5% players, and "git gud" if you aren't.
In Coil's case, the nerfs were done due to it being locked behind the story, and even the nyou'd still need a competent group to clear the end turns (T5, T9 and T13 post-nerf/echo is still harder than A4 on release), not solely for "making it easier" (this would be the case for the likes of Alexander savage). To most groups, I think A3s has more than overstayed it's welcome, and I don't think any amount of nerf will change that or reverse the damage it's done on some static groups or entire realms. Also to note that SCoB savage was left untouched throughout it's life. It was intended to be hard, but at the same time, there were other content available for the typical static (that being SCoB and FCoB), unlike now where they pretty have to do Savage (which is more or less tuned to be around SCoB Savage's level) if they want a raiding scene, because they sure as hell aren't gonna find it from normal.
