Yes, colonial mindset refers to the refusal of accepting other cultural backgrounds and cultural lenses, possibly due to an inherent belief that your own is superior or absolutely correct. This is not so uncommon in people coming from an imperial and hegemonic culture (like US). Edit: the colonial nature results evident from the fact that such position translates to the desire/pretense to impose a specific cultural lens or perspective even to facts, discussions etc. that belong to completely different contexts. The same attitude that colonizers have over the colonized.

I have already discussed the merits of the conversation, you refused to elaborate your thought in any way and you are limiting yourself to meta-comments that do not add anything to the conversation. In fact, you wasted several replies not saying anything but implying that your opinion is self-evident, which is a consistent symptom of that colonial mindset I was talking about.

You have been provided with a different, context-aware interpretation and you refused to engage with it at all, including challenging it, because being different from your own is automatically wrong and not deserving even of consideration. In fact you are still stuck on "racism against black people and indigenous people", which means you didn't even take into consideration that your interpretation of something happening in a cultural context you don't understand might be wrong. Of course you also refused to elaborate on the way this is racist, or better, you did in another comment in this post with an explanation that has to do with how racial stereotypes have historically been used to discard opinions of minorities, which while being true doesn't apply at all to this particular event and in general is quite tangential in Italian history, due to a completely different history compared to that of the US, especially when it comes to indigenous people.

So yeah, all in all I think you are showing a classic colonial mindset. Quite common in internet spaces where US culture is dominant, if it is of any consolation.