Comment by andrewaylett

The whole discussion hinges on the definition of "vehicle", which is not defined. If I take my definition as being "a vehicle that meets the definitions of a motor vehicle in the UK Road Traffic Act 1988, but not including those in use as emergency service vehicles" then the majority are indeed correct. And that's how I answered, because it's consistent with my expectations for a sign like that which has been placed by a human authority. If you choose the rather broader definition (from Wikipedia) of "machine that transports people or cargo" then more scenarios are excluded. But that's a more fuzzy definition too: is a remote controlled car (neither carrying people nor cargo) really not included in the category of "vehicle"? In practice you won't typically find humans placing signs with that intent.

So I agree with the parent and grand-parent comment. Without a context in which to understand the terms presented, even an apparently-clear statement and introduction can be entirely unclear. I suspect that if you pointed to an actual physical sign and a scenario unfolding in front of them, and asked people whether they objected, rather than asking as an abstract concept on a computer screen, you'd get a different distribution of answers.