I MEAN …
Also, on a more serious note, remember that Thalyssa and the Dusk Lily Rebellion never actually met the leaders of the Alliance and Horde apart from the undisputed religious leader of the Kaldorei, who were immediately hostile and dismissive of the Shal’dorei’s plights and needs and attacked them both politically and personally at every chance, and the Sin’dorei, who were immediately sympathetic and understood exactly what the Shal’dorei were going through.
Throw in that Thalyssa was super keen, despite all that, to reconnect with her ‘people’ and rejoin the world, and Tyrande literally slapped her down and accused Thalyssa of being an addict and no better than the Queen who, to Thalyssa’s mind, was the same one who tried to break the world and sacrifice all of its inhabitants to the Legion for her own gain.
And remember, Tyrande is the undisputed leader of the Kaldorei. Not even Malfurion can over-ride her orders.
Yeah, I’d be a bit leery of the Alliance too, especially if Tyrand was their idea of a ‘diplomat’ in this situation.
Then we see Thalyssa going to the Sunwell, and I want to point out, the Sin’dorei were her SECOND CHOICE here, meets another ‘champion’ of the Alliance, everything is going swell oh hey TENTACLE MONSTERS IN THE SIN’DOREI MOST SACRED PLACE, because of said Alliance Hero.
Jumping in with the Horde doesn’t seem like such a stretch after this.
That said, Thalyssa is nobody’s fool and is well used to the political hop-step-and-jump routine, and probably had chosen to join the Horde as much to stop both mega-factions annexing up what remained of her peoples’ territory, and probably had an exit strategy if the Horde did prove to be an unwise partner, much as she said to Rexxar and the Champion during the War Campaign, and was hoping that the Horde would provide at least the threat of retaliation if the Alliance, or anyone else, decided to come knocking on Suramar’s gates again.
Nobody was expecting Sylvanas and the Burning. Nobody. Even Nathanos was caught unaware, and he’s so far in Sylvanas’s good graces we’re probably going to get a dirty novel out of it. So trying to say “Oh hey you stayed, you’re OK with this then.” is a bit like saying people in North Korea are fine with the regime, and that’s why they stay, and not because they’ll be shot, their families murdered and have had a long history of tension with their neighbours and have been spoon-fed rhetoric that paints all other nations as enemies and cruel despotic regimes that make the current one look positively angelic by comparison.
Odds are if anyone left the Horde, just like what happened under Garrosh, you’d ‘disappear’. And unlike Garrosh’s rule, there’d be no wink-wink nudge-nudge toe the line comrade or you’re next for anyone else, you’d just straight up vanish and, if you were lucky, get used for spare parts for Sylvanas’s elite troops. If not, you’re an apothecary’s latest test subject.