Vol’jin had been someone she respected, although they had clashed on occasion. He lacked the abrasiveness that so often characterized orc leadership. And she had been genuinely sorry he had fallen—and not just because of the responsibility he had placed on her head.
Golden, Christie. Before the Storm (World of Warcraft) (p. 19).
The Undercity belonged to the Forsaken, and they were her people.
Golden, Christie. Before the Storm (World of Warcraft) (p. 18).
“Warchief,” he said, “it is time. Your people await you.” Your people. No. Her people were back in the Undercity, missing her and feeling slighted, unaware that she would like nothing more than to return and be among them once more.
Golden, Christie. Before the Storm (World of Warcraft) (p. 19).
She would have given me the Val’kyr for all eternity. None of my people would have ever died again.” She paused. “I would have saved them.”
Golden, Christie. Before the Storm (World of Warcraft) (p. 22).
And so on. Regardless of how unstable Golden makes her seem, there are several points that showcase how Sylvanas indeed did care to some extent about the Horde faction in general, and the Forsaken more in particular.
The fact that Blizzard needed only minor tweaks to ruin her overall character, doesn’t retroactively mean that Sylvanas had always never cared about the Horde as a whole. Even if she did so in her own twisted way.
We wouldn’t have instances like this one if that was the case:
Do not let da Horde die dis day.
It was a direct command from her warchief. And it was the right one. The Alliance effort below, valiant as it was, was dependent on Horde assistance. If the Horde retreated now, Varian’s army would fall. But if the Horde stayed and fought, then both armies would fall. Sylvanas had closed her eyes, each option unacceptable to her, but she made the only choice she could: obeying the will of the warchief, who later would die from the poisoned spear and, to everyone’s astonishment, appoint Sylvanas Windrunner as leader of the Horde.
She lifted the horn to her lips and sounded the retreat. She had told no one of the regret she had felt when, standing on the stern of her ship, she beheld the green smoke of the explosion below, where Varian had fallen, and wondered if she was watching the final, excruciating moments of a mighty warrior.
Golden, Christie. Before the Storm (World of Warcraft) (pp. 238-239).
And regarding the rest…well, i think that you are nitpicking. Although i do admit that we lacked back then much clarification regarding her motives (something Blizzard is currently grasping at to make her seem as if she never cared).
I’d say that back then she cared for it about the same as Lor’themar, Gallywix, and most of the races that came afterwards. Alliance of convenience and all.
EDIT: In short, I do not think that taking the current representation of a character that has been recently butchered and twisted to fit in the narrative, is a valid point to retroactively judge their actions more harshly.