No, that's standard business across multiple other mediums. Its only a matter of time before this goes to court, and video games follow suit with things that are more than likely not going to end up falling under "Fair Use" in court.
I highly doubt most of these types of videos would. Key considerations in fair use is how much of the content you're using, if you're transforming that content in your work, and if it's for nonprofit purposes. Most let's play videos that are monetized would fail horribly. AngryJoe potentially has a greater claim due to editorializing, but I think it's easy to say that he uses too much copyrighted content in his reviews.
It'd be like movie reviewers taking clips from the entire length of the movie, instead of 2 or 3 minutes of trailers.
I do doubt that Angry Joe videos will help to sell games like Mario Party, as it's extremely well established at this point.
It's sort of a hard argument to have, because the only demonstrable examples we have of where X videos for game Y boosted sales appreciably are generally smaller, indie games. The "exposure" argument matters much less for games that have massive marketing teams behind them.
The "protection racket" comparisons are amusing, because if you flip it on its head, AngryJoe is saying "Nintendo, unless you let me make money with your games, I won't advertise them on my channel." It's not protection, it's
licensing.
