They didn't say it would be the worst, just the longest.
They've also indicated that they aren't going to just keep madly raising interest rates, but expect to top out by next autumn:
"The Bank has done something it doesn't normally do in the published minutes of its decisions - it has given guidance that seems to suggest a peak in interest rates of about 4.5% next autumn.".
So it's far from scare mongering (on the bank's part, can't control how the media portray it), and more "this is not going to be a quick fix, we have some idea of how bad it'll get, and it's not as bad as the 80s. Please don't panic".
Quite a measured response in reaction to some bad news IMO.
Agreed with everything else you said. "This is not going to be a quick fix, we have some idea of how bad it'll get, and it's not as bad as the 80s. Please don't panic" is perfect phrasing. But saying it will be the longest recorded absolutely is fear mongering, and partly self-fulfilling.
There's also a big chunk of column C: the leading opposition party did a terrible job of opposing it. There was a chunk of the Labour party, including its leader, who also favor Brexit, albeit a very different kind of Brexit from the Tories. For them, it's more about anti-globalism and anti-corporate-control.
That leader eventually resigned, but by that point the damage was done.
I can't predict what would have happened if the Labour party had chosen to unify on a pro-Europe platform, but they were soundly defeated. The Tory party won resoundingly, and they had run on a pro-Brexit platform.
There is always skullduggery, but it's really just something the UK did to itself.
https://www.bbc.com/news/election-2019-50530163
The actual referendum was very close, and there was a lot of room for Labour to argue that it wasn't intended to be binding, or at least a Brexit In Name Only. The result was that Labour was creamed and the Tories got a real majority, whereas previously they'd been saddled with UKIP.
Corbyn also failed at the referendum, arriving at a belated and wishy-washy stance, and without compelling Labour to follow it. Had he resigned then, things might have been very different. Instead, he continued to lead Labour in a way that left people confused about where they stood on Brexit when put in the form of a Parliamentary election. Nobody could read the results as anything but "The nation voted strongly for Brexit."
I don't believe that really reflects what voters wanted, but elections are poor tools for sending messages. What they do is put people in office, and the people in office were people strongly for Brexit.
The impression I get was that by 2019, Remainers were tired of fighting about it, weren't enamored of Corbyn's version of Labour (Brexit was only part of it), and weren't going to rush over the LibDems.
And that overall, Brexiteers were enthused. Probably for very bad reasons, but they genuinely believed them. As for the original question, they might have been nudged along by some foreign propaganda and targeting, but it wasn't anything that their own leadership wasn't encouraging them to believe.
If you understood the political situation at the time, then it was all but obvious there would be a massive anti-establishment vote, facebook ads or not.
https://www.theguardian.com/uk-news/2020/oct/07/cambridge-an...