I think that this should be pointed out time and again: Arianna first tried to become a pundit of the right. She only became ‘leftist’ when she realized that there was a big market for it and no one was covering it even a little.
I remember seeing her in the 90’s during the impeachment on CNBC (couldn’t get Fox back then) and I thought she leaned right because she spoke against Clinton and for the proceedings to go forward.