People aren't talking about this. With Faction mods being meta for status and primary crit builds nowadays, Eclipse will more often than not be a better buff for weapons than Roar. Not to mention, it's a third of the cost, re-castable, and has a faster animation. Yeah, Roar affects ability damage and benefits allies, but there are a ton of frames that will still run eclipse, and probably a few new ones that care more about the major consistency increase than the power decrease.
(Though, as others have pointed out, a more proportional reduction in line with roar might still be worth looking at by DE)
And for people complaining about the Damage reduction being "worthless": 1. 90% extra DR on most tank frames is pretty dang great. It's a lot more appealing when it's consistent, and if you want DR from helminth, your alternative is Null Star. On non-tank frames, it won't necessarily save your butt in SP endurance, but in the other 99% of the game there is absolutely utility in "The damage increase isn't necessary/helpful ATM, so I'm gonna multiply my EHP by tenfold".
You're right about nourish too, but it's also something that DE themselves has said when it comes to their expectations for this nerf. It's not gonna dethrone Nourish, just rein it in from "I feel bad for not using it" to "It's strong, and does a lot, but it's not silly to consider alternatives" It'll still be the best energy subsume for anyone who doesn't want to sit still for dispenser. It'll still be the best version of "Cast to add elemental damage" especially since viral is super valuable even in small percentages.