An SUV with 8 people can get 200 mpg/person. The link considers average occupancy. Planes are highly efficient because they're usually full

Average occupancy is only relevant from a system view. If I'm driving my own car, it's the actual occupancy that matters.

So yes, if I'm traveling solo, a plane beats car. But with multiple people, car wins.

This doesn't change flying being a more efficient means of travel. Despite many incentives to carpool and take public transportation, planes are still more efficient because the high travel speed makes being packed like sadines worth it

How are you defining efficient? Airlines are time efficient but obviously not environmentally efficient.

They are environmentally efficient, see the link I posted. They're one of the most fuel efficient means of transport

The right motorcycle with two riders can get over 120!