Jeremy Corbyn and Boris Johnson are both Gemini. Leaders don't tend to be Gemini. It's an air sign, which is characterised by thoughts and ideas. You usually find Geminis being huge successes in media, where the capacity to shift according to their setting swiftly is valuable.
We've ended the Piscean Age and find ourselves in the Aquarian Age. Events beginning in the 1850s kickstarted a period of intense change and we're still figuring it out.