Once we've vaccinated against Covid enough, then Flu will be back (with social distancing relaxed). With Flu overwhelming the NHS every winter before this year when it's been Covid, I'm really worried that every November to March, we are going to be locked down again.
We've shown as a country (UK) that we're willing to accept lockdowns, strict or not, and frequently now, so what's to stop them doing it again? When they think that the NHS is going to be overwhelmed and they can argue that it's an emergency and in our interests / safety? And who would stop them if it isn't?