No, he did, here's where the confusion is.

Serinus is asking if the site in question needs to be compromised. In other words, can the attacker compromise a random site to fool your password manager into entering credentials for Gmail.com, or does the attacker have to compromise Gmail.com to do that?

Because those two attacks are very different levels of complexity.

And frankly, if someone compromises the site you're actually trying to visit, there's simply no defense against that at all.