> “Reasonable” is a lynchpin bearing an awful lot of load here.

No it's not. I could imagine sentences where it would be, but not this sentence. Here, watch me replace the word:

"99% of adults are not allowing their teenager to to experiment with heroin or giving their 12 year old permission to drive their car down the freeway."

Even if most people aren't ""reasonable"", they are whatever adjective that sentence describes.

It's a pretty generalized phenomena too. Few people actually think about the assumptions their arguments rely upon. It makes actual discussions difficult to have and leads to more arguing than problem solving

I'm sure you've got some hard data about the crazy amount of parents knowingly letting little Timmy develop an addiction to street drugs