I really enjoy how you concluded the article. However, there are some points you make which are completely ridiculous.
To claim that "Stoicism is For White Guys, by White Guys" when plenty of its core teachings, as you mentioned, are geared towards dealing with struggle, difficulty, and injustice, is completely disingenuous.
On top of that, I want to address this point you wrote:
"just choosing not to feel harmed is a luxury non-white people in our world are absolutely not afforded because they are harmed often and intentionally by social and political structures.
Similarly, they are not given free choice or will in how they choose to respond."
First of all, to claim that someone in the USA doesn't have "free choice" is completely false.
Especially considering that the meaning of the quote is referring to how we react internally, just indicates that you didn't even bother in trying to understand.
Quoting someone else that truly didn't have the "free choice" you're talking about, an Auschwitz prisoner:
"Between stimulus and response there is a space. In that space is our power to choose our response. In our response lies our growth and our freedom." - Viktor Frankl
And to top it all off you end up writing "It would be most fair to say that Stoicism itself is not the problem here, but rather the sound byte bumper-sticker interpretations of it, which have become so omnipresent. " when you just finished making a bunch of those claims by not looking at the general picture of things.
Once again, the way you concluded, in my opinion as excellent, the problem was that it didn't match up with this part fo the article.