because it wasn't the elvhen who attacked the titans, it was the evanuris. in fact, the elvhen were slaves to the evanuris, and she knows that. but she still - understandably! i wanna make it clear this is not a critique, it's a really good, interesting bit of characterization - blames all elves for it to a degree

the elvhen were victims of the evanuris, just as the dwarves were, just as the titans were. and it's this really messy place because, yes, the elves almost certainly went to battle because the evanuris commanded them to do so, and yes, the evanuris were not originally seen as gods but as generals, so one could assume free elves still willingly(-ish) fought for them

but ultimately, the destruction of the titans only happened after solas took form (and likely not immediately after, either - he took form to help mythal, and they developed the plan for the dagger and then created it, all of which likely took time) and solas was only called when elgar'nan was already beginning to exert control

really, modern dwarves and modern elves share a historical enemy, and it's not each other, it's the evanuris. elves have had an extremely hard history: they had what we can safely assume to be a period of freedom, taken away (presumably slowly) as they became enslaved to the evanuris. then solas' actions resulted in the unintentional destruction of arlathan and stripping the elves of their immortality, yes, but also a significant portion of their magical power, and killing a great deal of them in the process. the survivors were scattered and lacking a societal center, effectively displacing them as the "reigning race," although again, that's a faulty view of the elvhen even at the time, because they were enslaved by their own leaders

with the elves being disparate and scattered and the dwarves having been forced underground - and the kossith presumably becoming the beginnings of the qunari around about this time - the stage was clear for humans as a race to become the power in thedas, and they killed or enslaved many elves. correct me if i'm wrong, but i don't recall anything about humans enslaving dwarves: of course, trade with dwarves was necessary due to lyrium, and the cultural pressure for dwarves to stay underground (likely stemming from a fear of reprisal should they travel back into what had then become elvhen territories) means that surfacer dwarves must exist largely unchallenged. but elves provided no material benefit to humanity, and so were treated as interlopers, outliers, "savages," or - horribly - opportunities

and it's really, really interesting to see lace have to grapple with all of this, because she obviously has a great deal of sympathy for slaves, but she seems hesitant to connect the dots about the elvhen. she acknowledges that solas was right to move against the evanuris and try and free his people, but she still blames elves as a whole for what became of her people