If I were to take a guess, it might be because the quoted text comes across as conspiratory and opportunistic. It's not that Weinstein shouldn't be free to post tweets about what he likes. It's just that it had no relevance here.
If it isn't obvious, then I'm not sure what I can add to it. To each his own.
Edit: I realize this can come across as rude. In short, the unproven "mysterious" GU stuff is something he is trying to advertise. McAfee was recently found dead, and it makes the news. The tweet is a weird rambling that somehow manages (tries to?) throw in some more conspiracy and tie it to GU. In any case, bs alarms are ringing. He expects people to care about GU, but I'm not buying it.