I re-watched this recently, actually. I agree that Dawkins won the debate ... but I do think that McGrath had at least half of a good point. Namely, when he said, to paraphrase from memory, "Probable or improbable... the question is *is* there a God?" .... the part that I think is half correct is that I don't think focussing too strongly on how probable it is for God, a human eye or anything else to pop into existence when nothing like that works anyway, is that important and I think that the real question is whether it makes sense for there to be such a God at the beginning. Dawkins at one point alluded to the fact that some theists think that God is actually ultimately simple. He pointed out that an ultimately simple God probably can't do the sorts of things that the God of Christianity is supposed to do ... but I still think that is the most interesting question. And I think that the half of McGrath's point that he got wrong is that it's not really the case that probable *or* improbable the question is is there a God because if God is *completely* probable or *completely* improbable then that's clearly relevant to whether a God absolutely does or doesn't exist or not because absolute probability and absolute improbability is just one and the same thing as absolute existence or nonexistence. But I'm sure he meant to exclude a probablity of 100% or 0% when he was asking an absolutist question anyhow.
I agree it's an interesting discussion. I watched it many times back in 2008-2010 back when I was one of Dawkins' millitant sorts of 'New Atheists' after reading his book 'The God Delusion' when I was younger. Nowadays I am much less militant, much more apatheistic and much more philosophical and although I'm technically an atheist I don't see my atheism as important anymore ... I rather just see my atheism as a probable side effect of other things that are important to me (e.g, empiricism and rationalism) rather than it being something that is anything valuable in and of itself.