The commentary around the table of results (which is a bit buried in the middle) is propaganda, I would say. So I tend to focus on the table and largely ignore the surrounding text.

One of the reasons I said YouGov is unreliable is that a major bias in any survey is determining who you ask. Most YouGov surveys are based on filling in online questionnaires, so you suffer from all the 'self-selection' problems.

As we are coming up to the five year anniversary of the vote, ask "how's it going?" is quite a reasonable thing to ask.

I agree with Nigel that it is interesting that there is a string difference in the opinion of Conservative and Labour Leave voters. There are probably dozens of factors in play. One is that with the Conservatives in power, it is much harder for Conservative voters to say "this is going badly" whereas there is quite an incentive for Labour voters to say 'this is not the Brexit I voted for.'

A second one is that it is very likely that Labour Leave voters and Conservative Leave voters agreed that the UK should leave the EU, but they genuinely had different ideas about what should happened next. I suspect, but do not know of course, that many of the Labour Leaves felt it was the best way of protecting UK jobs (i.e. essentially protectionist), whereas many Conservatives were much more 'free market' inclined, and so opposed to protectionism.