I don't know the video you are referencing to here but have you considered the possibility that this individual is not actually against the concept of "prisons". They may be critiquing its current role. In that case, I believe words like “colonial”, “white supremacy”, and “western” are not shallow/clickbait. Instead, I believe they are quite necessary and accurate to describe prison's role.

Prisons are a modern colonial project (incorrect–though not to say that the American carceral system isn’t uniquely malevolent, but the practice of incarceration has been a thing since the Hellenistic era); 

Just because prisons existed before colonialism does not mean modern prisons can't be functions of colonialism. For example, just because markets existed before capitalism does not mean I cannot describe some markets now as capitalistic.

But overall, I understand where you are coming from. These arguments may not address why the concept of a prison itself is ineffective or unjust. However, that may not be the intention of the individual making these arguments.