I know you have strong feelings towards Corbyn but the point is valid. He is Marmite. If they got someone who was a bit more 'magnolia' that doesn't have such strong views* or does not share them with the public at least, then you possibly wouldn't be instantly switching off one half of the voters. *I'm not saying it is wrong to hold these views, they are very decent after all.
There are lots of people that don't like the idea of strikes, they don't want to think about using a bus/train/health service and finding that they can't or it's bare bones that day. The Tories will play up to a vote for Labour could cause us to lose our nuclear capability, even though this would be wrong as the party have overruled. But the genie is out of the bottle.
So basically Labour will sweep their areas and the tories theirs and never the twain shall meet. The only variable is how much the LDs and Brexit party eat into that vote and take the odd seat.