Also there is this - decided to read it when I was checking up on facts:

"Cuban has repeatedly described himself as very lucky to have sold the company before the dot-com bubble burst. However, he also emphasized that he hedged against the Yahoo! shares he received from the sale and would have lost most of his fortune if he had not done so."

Sounds like he doesn't care for Trump much and his politics aren't conservative which explains a lot of comments in the thread.