See the difference now? you can't even obtain my private PC's IP address, without some serious big effort, probably NSA level surveillance is needed. Then you need to somehow attack my firewalled PC that does not offer any service to the outside, which is actually not as easy as you think, it's probably nearly impossible to do so.
What are you talking about?
Why does a hacker even need to know your IP before you are compromised? Your computer is full of security vulnerabilities. Why do you think it is constantly being patched? All someone needs to target you is your email address or to know what sites you prefer visiting.
How do you hack 51 delegate's private computer without knowing their IP address, even assuming their computer all have vulnerabilities?
having OS security patches doesn't mean you can be hacked while firewalled. Mostly these vulnerabilities happen under a very specific scenario, mostly requiring you to visit a malicious website or use a specific application/setting. Otherwise you could just pick a random IP address and hack into it? of course not, the reality is your private firewalled computer is very much safe even when you are connected to WAN, as long as you don't install virus/trojan yourself.