Good points here, ronde_des_sylphes although a few with which I might take some issue.
Corbyn was indeed miligned but has was also his own worst enemy, principally in failing properly to address the anti-Semitism issue (which was not, I believe, as widespread as some Labour detractors, including a few from within Labour itself, were determinde to make out) and, perhaps worse still, to sit on the fence over Brexit so that people didn't feel that they had any idea where Labour stood on this.
Boris's transparently false bonhomie, along with his at times compromised articulacy, fools few people and it's largely a thing of the past in any case now that he's had and largely recovered from COVID-19 (not that I would have wished it on him).
Had a majority of the electorate perceived the last GE to be mainly about Brexit (though why that GE and not the 2017 one, one might ask), it could have voted with its feet for the Brexit party and, had it done this, Brexit would have been as clearly revealed as the predominant electoral issue of the say as Thal claims it to be despite that party having performed dismally; clearly, no single issue preoccupied voters any more than at any previous GE.
The notion that those who complained that Eastern Europeans from EU were coming to take the jobs that, for the most part, they didn't want to do anyway is not even geographically accurate; there are no Eastern European countries in EU, for Ukraine, Belarus, Moldova, Turkey, Armenia, Azerbaijan and Georgia are central European ones and the five "stans" Eastern European and none of them is an EU member state. We still have a problem now that foreign labour can't get to UK to do fruit and veg picking.
Yes, there have indeed been some unsavoury racist expression in certain quarters but even these have been largely inconsistent in their application. How often, for example, have most people in UK heard racist abuse of Portuguese, Danish, Swiss, Norwegian, Finnish, French people? - it's usually mostly people from what some think of as "Eastern Europe", the Middle East and the Indian subcontinent.
Anyway, COVID-19 seems now largely to have overtaken much Brexit negotiation and the prospect that the UK government will adopt a default no-deal stance if it can't be completed by the end of this year (which seems almost certain) will by no means endear it to the electorate; plenty of Brexit supporters do NOT want a no-deal Brexit. One such said to me that, whilst the government has made Brexit possible, it can no longer be trusted to negotiate one with proper deals in all areas; she made it quite clear that she does not want a no-deal Brexit and would never again trust, let alone vote for, a party capable of nothing better than achieving or endorsing one.
Best,
Alistair