Earlier quoted context omitted.
... This entire discussion IS about bad software that DOES harm you, and you rag on the measures to specifically protect against something like that? What the heck?
Yes, I'm not saying there is no harmful software, I'm saying these kind of "protections" are the wrong solution. The same people who install blindly any add-ons will also install any exe-files if the promising website tells them to because the browsers add-on-system does not provide the required mechanics. So the next step is to disallow exe-files. But of course you can let the exe-file get signed for a "small" fee..…
Users can manually choose to run unsigned executables. Please stop spreading that FUD.