"people aren't going to vote for" Corbyn.
Aren't they? I would. I think you'll find plenty of the people on this thread might.
The point is, you don't know what's going to happen. He might become leader and shake up the whole party, stepping aside for a younger leader in time for 2020. He might have all the vim and vigour needed to do it himself. He might be the greatest opposition leader of all time. The Lib Dems might reinvent themselves or the Greens or all of the left wing parties could work together and the face of politics could change. We simply don't know. We can can vote for what's on offer right now and do so according to our principles and beliefs.
Or you can make sweeping generalisations, decide there's no point, write off the bit of hope being offered and we'll all just give up now.
His age does not prevent him from giving it his all right now. Who the heck knows what will happen in five years. We have to do something right now and then react to what happens later, later.
I will be voting for a leader of the Labour Party for 2015. In an election, I'm not so foolish as to vote for a man. Or his age. Or his ability to eat a sandwich. Or his sexual history. Or his family.
I like what Jez has to offer right now.