Agree. By entering the private keys at any point, security is compromised. So all those web3 apps will require the user to use a hardware wallet in order to be safe, but that will not attract too many people, because most people want things simple and friendly. Therefore web3 will either be safe but with few users, or it will be massive but also will have massive security issues. btw the guy from the video was the one who cracked and stopped the wannacry ransomware attack (first wave) on 2017. That´s why I watched it, despite the clickbait-like first screen.