you mean mixed biscuits? well yeh you will find yourself agreeing sometimes with people from different political positions but mostly it's because of different motivations and reasons. it's very well possible to criticise the european union from a leftist position, or to criticise the covid lockdowns from a leftist position. in fact, i feel like especially the left should, but they don't and that's one of the reasons i don't care about much of them.
Maybe it's different for someone not in the UK, I dunno. But comparing the EU to Nazi Germany has been a favourite bit of rhetoric for politicians and journalists here who are themselves on the hard (or far) right for decades. The campaigns to leave the EU, especially the one led by Nigel Farage and his lot, focused overwhelmingly on immigration, and particularly immigration by Muslims, despite the fact that Muslims are generally not coming here from Poland and Romania. But they made a huge deal out of Turkey's supposedly imminent joining of the EU, which oddly enough still hasn't happened in the eight years since the referendum and shows no sign of happening any time soon. Predictably, there was a big rise in hate crimes against immigrants in the run-up to the referendum and its aftermath, regardless of whether they were from EU countries or not.
As far as us "dodging a bullet" goes, nothing has got better here since 2016 and a load of things have got measurably worse. The shortage of doctors, nurses and carers, which was already bad, has got a lot worse, and since we're no longer covered by EU environmental regulations there is barely a single major river here that isn't choked with farm effluent and human shit.
So the idea that any "left-wing" person could look at this and say "This is a good policy and I'm glad it's happened" strikes me as completely fucking insane.