The same stuff has shown up in all polls across all pollsters during the pandemic, and YouGov don't make their money by acquiring useless, inaccurate information. The public are just a bunch of reactionary weirdos.
I think I've said this before on here but imagine a street somewhere near you, think of each house and think of all the monstrously dull (often old) people who live in them. These are the people racking up these numbers on polls.