Sorry, it's generally a pretty standard policy among many sites that allow video which I assumed most people would know. This is 1 of those things that's void of laws, it's a YouTube policy, doesn't matter if someone's country allows it or not, similar to the fair use laws. But this is their privacy guidelines/terms thing:
https://www.youtube.com/static?&template=privacy_guidelines
"
How does YouTube determine if content should be removed for a privacy violation? For content to be considered for removal, an individual must be uniquely identifiable by image, voice, full name, National Insurance number, bank account number or contact information (e.g. home address, email address). Examples that would not violate our privacy guidelines include gamer tags, avatar names and address information in which the individual is not named. We also take public interest, newsworthiness and consent into account when determining if content should be removed for a privacy violation. YouTube reserves the right to make the final determination of whether a violation of its privacy guidelines has occurred."
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What does uniquely identifiable mean? To be considered uniquely identifiable, there must be enough information in the video that allows others to recognise you. Please note that just because you can identify yourself within the video, it does not mean you are uniquely identifiable to others. A first name without additional context or a fleeting image, for example, would not likely qualify as uniquely identifiable."
So since they're doing reaction videos which is going to show people's faces, where others would have to be completely blind not to identify someone if they knew them, it will go against YouTube's privacy policy, if that person hasn't given consent or files a complaint. Even gaming channels have to obide by this when someone else's voice is being used specifically for the video.
Also note: "
What if I've obtained consent from the individuals? Unfortunately we cannot accept or review agreements granting consent before the video was uploaded. Thus, we may still have to remove your video based upon the complaint." This is why you probably see many prank channels placing the parts where they show people the camera.
Either way he's gonna have to follow YouTube's policy regardless of his country's law or monetisation and by the looks of it; his own country's laws seem a little strict on the whole matter to begin with.