This is honestly too much of a nerf. I don't care if she has a high winrate in Ranked. She wasn´t even used that much in recent tournaments anymore (meanwhile Cypher had a 95%+ pickrate) and that is where Riot should focus their balance philosophy.
We balance around pro play and matchmaking separately - if Sage needs some buffs on the pro side of things, we can do that.
The reality is that Sage has been substantially stronger than any other agent in the game by a wide margin since closed beta, while also having an absurdly high pick rate compared to any other agent. If she ends up being too weak after these changes, we’ll ship some buffs to get her in the right spot.