UK voters (imho) were still stinging from the economic decline and austerity measures post-2008, and were led to believe that a divorce from the EU would restore their greatness. Now that that's been demonstrated to be a delusion, and with covid-related economic collapse piling on top of Brexit consequences, UK voters might be open to a dice roll.

This is obviously my idle speculation, and I think the UK voters would never be allowed to vote on such an opportunity anyway. Still, I think if it happened it'd be great for everyone.