Uh, no. He thinks he's one of the top three most knowledgeable people (meaning overall knowledge) in the game industry. He didn't say anything about being one of the top three Japanese developers.
Itagaki said:
...When it comes to knowledge for example, of war I think Im one of the top three people in the industry.
And about the Japanese industry failing -- the interviewer introduced the topic while mentioning that many of Itagaki's contemporaries think it's true. Surely it can't be such a ridiculous belief if Japan's leading designers think it's so.
And why was his political analysis humorous to you? Judging by your reading comprehension, or lack thereof, Itagaki knows more about politics than you ever will.