>Microsoft does something similar with Windows Defender: you need to buy a developer certificate that can be revoked at any time if you want to distribute your app and have users be able to run it.

Clarifying: you CAN run an unsigned app just fine on Windows. A lot of freeware/"indie" (for lack of a better term for small software) programs run just fine, the only thing that happens is the user recieves a warning they have to press "Yes" on (which 95% of people do, because That's The Windows UX[patent pending]).

Depends, I ran into this issue[1] a while ago with unsigned binaries.

[1] https://news.ycombinator.com/item?id=40815488

They obfuscate it more than just pressing "Yes". You get a big warning saying Microsoft Defender has protected you, and the only clear option is "Don't run"

https://cdn.advancedinstaller.com/img/prevent-smartscreen-fr...

In order to run, you have to click on "More info", and then a second "Run anyway" button appears.

There's way more than 5% of the Windows userbase that gets confused and can't get past this warning.

In that case they wouldn't be stopping anything, since they haven't started signing anything yet.

I also haven't seen any specifics on how that system is supposed to work, but have seen a lot of speculation and (perhaps not unwarranted) fearmongering.