Alas, he is probably just a typical young person - apologies, kvalidir, I know you're not all like that, but it is quite common: see some complete balderdash, think "Wow, the world must hear this!" and instantly fire off tweets that make the original lies seem even more scandalous.
You'd like to think the political classes would by their nature come from people who were more cautious and showed some signs of adult judgment. But this is probably wishful thinking. They come from people who want power.
I expect Labour would prefer him to remain where he is, always a potential embarrassment to his party.