The way that I understand it is that us immunised folk will be protected from severe reactions and the nut jobs will go round infecting each other and getting sick.
I will be getting vaccinated as I am 50 and understand the risk. I think it is a different question if I was 20 and I was juggling unknown downside (long term effect of vaccine) with minimal upside (protection against a virus that wouldn't affect me).
I wonder what the vaccine take up rates will be amongst the young? I would be surprised if take up rates don't fall as the groups get younger and younger