Your argument seems to be that because there are multiple ways to exploit people that closing any of those methods is not useful. I shouldn't have to explain why this is not a meaningful argument.

What I will say is that in many cases an attacker is far more capable of MITM than they are of posting forum comments, or otherwise convincing you to click a link. A phishing campaign is noisy - you are often alerting many parties that you're malicious. MITM within a network is much stealthier and you don't have to rely on users clicking on anything.

Really, they're just completely different attacks and the existence of one has no bearing on the other. TLS on every page would close off real attacks and, if it forced attackers to use noisy methods like phishing, that's a huge win.