Ableism and racism are two things that actually tend to be quite linked with one another, as an example my people were decreed to be mentally disabled on a racial basis and subjected to forced sterilizations during the eugenics period.
But I do indeed agree that the dynamic between sundered and unsundered reads more like ableism than racism, specifically because, while both terms focus a lot on bio-essential traits, racism is almost always laced with a culture, religion, and language element too, which is completely absent from Emet's framing of the sundered vs unsundered (the impulsivity he criticizes the sundered for is more connected with neurodivergence than culture).
Now the dynamic between the playerbase and the unsundered however, that one reads like unintentional racism to me (please keep in mind I am not trying to say people are being racist here). Everything from the "they were no angels" rhetoric, to the "evil savages" rhetoric, to the "they were biologically inferior due to dynamis" argument, to the "it was a necessary evil/it was for the greater good" argument, to the "they were doomed anyway so it's fine" argument. It is all rhetoric and arguments that the settlers use to justify what they did to my people, which is quite uncomfortable to me since the ancients read almost like an indigenous-coded people to me.
To explain a bit more. On the "they were no angels" one, every time my people try to point out and celebrate the positives of our culture, the settlers come along to remind us of all the bad parts, as if to blunt the horror of the genocide they committed against us.
We're not allowed to ever, ever just talk about the positives as a way to lift ourselves up after the endless demonization and dehumanization we're subjected to.
For the "evil savages" one, it's the "harsher" so to speak of the above one, actively putting us down by claiming we were evil, murderous, degenerate savages who simply needed to be "civilized" or outright removed for both our own and the rest of mankind's sake (in case you are wondering how this applies to playerbase criticisms of the ancients... I have seen an immense amount of "they deserved it cause they were evil/callous/uncaring" arguments).
I don't think I even need to say much on the "they couldn't use dynamis" argument, because that's literally just unfiltered eugenics.
As for the "necessary evil/greater good" argument, yeah I've heard that one before so many times as well, we simply had to go because our genes were polluting mankind and it was weakening mankind to a point where we were a threat to the future of the world, that or our "primitive ways" would stifle their beloved "progress" by "occupying" so much land that could be "developed" so therefore us and our culture simply had to be removed "for the greater good".
And finally for the "they were doomed anyway" argument, this one is literally just "I don't consider you alive therefore it's not murder", because truth is we're all doomed, we're all gonna die one day, every breath you take is just you "delaying the inevitable", every culture, every species, will go extinct one day in the future. But that is no reason to abandon the present, every moment of every life that is currently alive is precious and irreplaceable, they deserved to live out their lives and meet whatever natural doom would come to them one day.