Save your words. You are not being a gentleman. People with good sense doesn't trust or belive who is too rude and agresive (and never they give data to prove their arguments).
You can tell your own vision about the past, and I don't mind if it is happens in your game, but a company publishes something something what promotes negative tropes about the past of my people, then it is different, because then it is my business.
I don't want to cause troubles, but I can warn your prejudices against my people aren't wellcome. Self-criticism and humildity are necessary to not repeat the same mistakes of the past, but you have forgotten a very important lesson in the fight against the fanaticism and the hate-speech: the respect for human dignity. Without this you are like the characters from "Games of Thrones" causing damage against innocent lifes. Without the respect for the human dignity all the efforst to be inclusive and politically correct are useless and worthless. Self-criticism and humildity doesn't mean allowing to be emotionally manipulated appealing the shame and guilty feel.
I am not impressed at all. Other have said the same speech before than you. If I could I would explain the reasons because The accusations are false, exaggerated or omit certain circumstances mitigating guilt. And accusations lose credibility when the actions of others who are much worse are blatantly omitted. I dislke that annoying double standards, I can trust nobody who uses two different yardsticks to measure
You should take care when you talk about the past, because you may be very ridiculous when the other knows it better than you. I am not so proud, but I am sick with the Hispanophobia, I see we weren't so bad, even we were a shinnier star, and the black legend is using the same mechanism than the psychological abuse. I don't want to feel guilty and ashamed any more only because others want to destroy my honor and prestige. I don't need more advices from people who don't respect and don't deserve my trust.
Maybe a players feels inspired in the martyr saint Pelagious of Cordoba, killed around the year 926 AD (only 14 years old) to create a spirit patron for her paladin PC, or a DM could use the story of the martyr saint Eulogius of Cordoba (killed in 859) to create a relic very useful agaisnt undead and infernal enemies but other players may feel unconfortable. We should show enough empathy to understand the feeling by the others. Even if your conscience is clear, you safe you have done nothing wrong, you have to face the consequences of your actions.
Some tropes can be showed if there is no an abuse. And also we should add "positive tokens". Some players wanted a group of heroes style Captain Thunder (a Spanish strip comic, style Prince Valiant. It was very popular in the middle of XX century), and others would rather a group of survivor characters style Makinavaja (a satiric comic whose main characters are criminal slums). Or you can add a group of nPC halflings with that very funny Andalusian accent. This can be wellcome even by Andalusian players, but if you abuse too muchthen it stops to be funny.
And when I say "positive tokens" I mean we have to add characters from the same origin but showing positive traits. Let's use this example. In the 1998 animated serie "Bob Morane" the main antagonist is mister Ming, with clear Asian origins. This villains has got a daughter who doesn't approve her father's actions and she is in the side of the good guys, helping the main characters against the big bad guy. This daughter is an example of positive token.
In the first years of the sci-fi comic Buck Rogers the antagonists were the mongols. If today a RPG of Buck Rogers was published again then we have to add a group of Mongol rebels who help the heroes against the tiranny. Have I explained it rightly?
Or let's try with other example. You can create an adventure where the antagonists are morrion-wearer vampires but then you should add "positive tokens" and these would be morrion-wearer vampire-hunters.