Chris that is my point - it is said when something would not be welcomed (as Andy Burnham said about another lockdown in Bolton) and a lead balloon would do down rather than up so it wouldn't be a good idea or go down well.
it's playing on two different meanings of "go down". If an idea goes down well, it's like good food that goes down into your stomach well. But then the sentence switches halfway through to show the comparison isn't with a successful meal, but with a failed balloon launch.
I can see what you're getting at lankeela, but I believe you're over-thinking it. After all you wouldn't say "That went down like a helium balloon" would you :-)