Okay, but.
Are they Marxist-Leninist? Pro-China? Socialists? Anti-capitalists? Looks like: yes.
Was the whole thing founded on the grounds of free, shared things and anti-corporate thinking? Also yes.
Do we absolutely know for sure that the ML domain was chosen because of this? No, because the above sources (or any source I ever saw) confirms or denies this claim. (If there is something specifically about the TLD, please share with me.)

I’m not saying it stands for Machine Learning. I’m not saying it stands for My Love or Mah Lord. But I also wouldn’t say that it for sure stands for Marxist-Leninist. We can assume, but we don’t know for sure. Maybe it’s because it’s free, maybe it sounds cool, maybe it’s Maybelline. We don’t know this specific aspect of the story. (As far as I’m aware.)