It might help to read it once more then 🙂

Not entirely. CF can protect you from DDOS of up to a few millions of calls per minute. Your home router would melt with that traffic. They also act as a firewall if you enable the proxy dns feature. They do a sanity check before forwarding the call. Also a home router cannot do this. And there’s more.

It’s pretty common https://en.m.wikipedia.org/wiki/Mononym