Let me ask you a question MG. Do you continue to not come into contact or have any visitors or visit anyone else? If yes, they why is that different now, than then? Double vaccinated people can still get and spread the virus. Also there's a large percentage of the infected that are asymptomatic.
To Edit: I meant to say if you are having visitors and going out with friends and extended family what has changed from the quarantine lockdown that makes it ok to do that now. It's a general question and doesn't just apply to the UK but applies to all Countries and all peoples. Sorry for the confusion.
Its my decision, mainly because I'm old and have heart issues, but I continue to stay away from others. No visitors (even my kids). I don't go to shops. I did dine out with my kids & partner at the end of August but the kids both took lateral flow tests beforehand and we sat in the open air. Right now in the UK a large percentage are vaccinated and if a vaccinated person gets the virus they are much less likely to become ill so that is the main difference. However, back in March last year the virus was rampant and there was no vaccine so the neighbours I mention were quite literally risking the lives of others.