Rather than criticise this young man for his youth, we should celebrate it. Democracy in this country is dieing from lack of involvement. If this chap can encourage other young people to take an interest in the governing of the UK, at any level, even just to turn out to vote, it will be fantastic.
As to his lack of experience, remember it was older, more experienced politicians who got us to where we are now.
Experience of getting it wrong is not much use.
To any of his critics within his ward who failed to vote, remember if you don’t vote you have no right to complain about the result!