I think jumps the gun a little.

When sharing a network, there are other attack vectors into people's unhardened laptops except browser MITM. Do you have any unprotected shared folders? Can someone brute force your login via RDP? Can you account for all the listening ports running on your device?

A NAT provides strong protection by simply firewalling you from the outside world. It's so common that the focus (rightfully) zoomed in on MITM as that is the only thing "left", but in a shared network, the adversary may reside on the inside nulling that protection. Most users have not taken precautions against this.

Oh, and shoulder surfing.