You're the only one who asserted a percentage. So allow me to clarify, when I wrote that comment I had no belief that a law need be 100% effective for it to be a useful law. I also believe there's a lot of room between 100% effective and "backfiring". I don't believe this is a binary situation but there's a spectrum (that isn't one dimensional)

I hope with this added context that my previous comment will make much more sense and you can interpret it closer to what I intended.

I'll just add, I don't think most people work in those absolutes. So I'd be wary of jumping to the extreme interpretation. People might interpret you as being disingenuous and using the logical fallacy "logical extreme" or "reductio ad absurdum". But I'm pretty sure you're not doing that because then I'd be grossly misinterpreting you, right?

I misread your "It always backfires" comment as making something illegal always backfires, rather than the desire to make things simple always backfires (note that "always" implies 100%). So now I see all you're saying is "be careful", which is fine.