Nothing new though is it?
People want someone who looks like a Prime Minister and sounds like a Prime Minister. Image is everything. Look at how Theresa May softened her appearance. Look at how Boris shaped his prior to the leadership bid. Look at how Osborne changed his image in anticipation of taking the reigns from Cameron.
In an ideal world full of principles and value, what someone looks like and sounds like in politics wouldn't come into it, but we don't live in said world - it's partly why Labour have been out of power for nine years, because the Labour membership somehow concluded that Ed Miliband could be Prime Minister and when they were emphatically proved wrong, they replaced him with Jeremy Corbyn.
I find it inconceivable that any party should elect a leader without first asking, does this man or women look and sound like a future PM? Because if the answer isn't a resounding yes, you risk hamstringing yourself from the get-go. It's a dose of populism. And you have to be prepared to take your medicine if it means getting you into power.
Now watch Corbyn and his ill-fitting brown suits prove me wrong.