I'm skeptical about the alleged Mao line. Would like to know what quote they're thinking of because from what I've read of Mao, the likelihood would be that if he's talking about racism in the US at all, it'd be about the dialectical aspect of it, which is not the same as excusing people of any responsibility (which would be a mechanical materialist view).
Mao was a scientist in his own way, as is the practice of ML more generally, and it's important people not confuse a scientific socialist analysis with a priest absolving people of sin.
I'm also not sure I understand the criticism included of Parenti. He was not perfect in his takes, but what is "Chomsky" about pointing out that the US empire sends its own people to die in foreign wars? This is part of its dynamic. Parenti also had things to say on how the "third world" is "not underdeveloped but overexploited". He was clear on the damage being done there, as far as I'm aware.
Prysner I have nothing to say about in the specifics. I know little about him and if he's a veteran of the US military, it's definitely possible he has some baggage and biases that steer some of his takes in a sus direction. But it could also be he is being misrepresented, considering how odd of a portrayal of Mao and Parenti the take seems to be.
I'm also just like "???" about any take with an argument that is "read too many books." People need to read more, if anything, not less! So many "hot takes" on the internet would be so much sharper if they had strong study and comprehension of that study behind them.