A simple “you’re not alone and I do know things are really hard at the minute and I really want to be able to change that for you and people like you” just feels a little better than “my 6ft 1 lad won’t fit in a onesie” or whatever words to that effect he mumbled.
But she hadn't finished talking. Answering her question before she's finished is rude.
Telling a story that makes her feel more comfortable about continuing is what I'd expect of a really good communicator, and that's a category I definitely wouldn't put Starmer in, so I thought he came across pretty well here.