‘Average’ does a lot of heavy lifting here. Let’s get this straight: you and I would live in squalor, if we would live at all. The 1% would have become the 0.01%, living in splendid wealth in the few remaining habitable places on the globe.
Humans are dying NOW. Heat related deaths are soaring, equatorial regions are close to uninhabitable already. Anyone who can read graphs and plot trajectories can see this is ending badly. The most common phrase from climate scientists lately is "It is happening much faster than expected".
Close to? It's all but a certainty. The global world order we enjoy today would also be as good as gone. We're talking large swathes of the globe being uninhabitable by humans.
I'd say an average person has at least a 40% chance of being dead at +4 C above preindustrial baseline. Agriculture would be nigh impossible for starters.