Apple has become more restrictive about this. Out of the box, apps from unidentified developers are not allowed to run. The user has to explicitly allow them. (For macOS Sierra it has become even more cumbersome to run these: http://apple.stackexchange.com/questions/243687/allow-applic...)
I think it should work good for non-IT users. But for developers who depend on a lot of FOSS, this creates a problem. Does anybody know if Apple allows OSS developers to have free accounts on Mac Appstore?
" Out of the box, apps from unidentified developers are not allowed to run. The user has to explicitly allow them. "
I understand this, but this is an extremely low barrier - especially if the user actually wants to run the dam software they just installed, they have to 'allow it to run'.
Who's going to install software and then 'not allow it to run'?
I don't think this security feature has much effect at all.
Apps installed on Mac or Win can pretty much do anything they please.