The vote was to leave or stay - there was no mandate for or against a specific relationship to the EU before even considering how drastically opinions have shifted since.
Then do you not support another vote that provides this option?
> how drastically opinions have shifted since
There is a way to conduct a poll that represents the engaged electorate - have another vote.
But in the meantime it is also entirely unambiguous that there is a clear mandate for a closer relationship - the gap is so huge (much larger than the support for the current status quo ever was) that there's no real need for another vote for that and voters can punish parties that support it at the next general election.
Of course it would be, but people would need some kind of understanding on what basis that would be on.
> It's pretty clear from polls [..]
I think there is only one way to know for sure.
> But in the meantime it is also entirely unambiguous that there is a clear mandate for a closer relationship [..]
People of the UK do not hate Europe, but there is evidence to suggest that people of the EU do not view the people of the UK favorably [1]. But I think the point of sovereignty and cost is a big one.
[1] https://uk.news.yahoo.com/yougov-survey-eu-crisis-uk-1209146...