Not to point out of the obvious, but when exactly did this happen? Nor was it even true back in Cata. What EoN literally says is that the Forsaken have now become her “Bulwark Against the Infinite”. Nowhere does it indicate that they are any less of tools than they were prior, they just serve a different purpose. Nowhere in that entire short-story does it indicate that the Bulwark was meant to protect the bodies that comprise it, either from others or the Maw.
And Cata hits, and if you just assume she’s putting on a show for the Forsaken (like she had apparently been doing since WC3), then a lot of her words come off rather empty. And if you look at her actions for what they are alone, then what she is functionally doing in Cata is sentencing hundreds of people to the afterlife she is desperate to avoid; in order to further build up the power of her bulwark. She is building up her “meatshield”, and reinforcing her motivation from EoN.
Then we have what she did to Koltira Deathweaver in Cata; we have her erratic behavior in War Crimes; and then her downright sketchy actions in Stormheim. All of this content does contribute to the Sylvanas we saw in BfA. That even if we didn’t know the outcome, this sort of extremely nihilistic, selfish Sylvanas (the one we saw in EoN) was still a very real path for her. A path where again, she’s just using others as tools for personal objectives, then discarding them the moment they cease to be of use. Just as she did with the Forsaken against Arthas. Just as she did with the Forsaken and Horde in BfA. Her Bulwark (which had grown to include the entirety of the Horde after she became Warchief) was no less just as tool than her arrows were.