I was wondering if a different teaching approach might help. Alec is letting Joe go in blind, that helps Alec assess what Joe needs to work on, but maybe flip the order and have Alec talk through a pace lap demonstrating the ideal racing line, pointing out the braking zones, what gears and when to shift, and how to exit or setup of a complex of turns. Then Joe can go try to replicate it. Eventually Joe will understand how to find the ideal line and braking points on his own but I think this could speed up his learning curve and potentially reduce his embarrassment/frustration. Just a thought, you guys are doing great content here!
I think the hardest thing about going from a go kart to a sim is there's no sensation of movement, no G forces on you. So you have to rely upon your other senses like your eyes and ears, but maybe most importantly the force feedback through the wheel. You also need to understand the tire grip, what causes understeer and oversteer, and weight transfer like Alec pointed out. I would also say VR can help with the depth perception issue many people struggle with understanding where they are spatially on the track.
That’s why I love karting and don’t really enjoy sim racing. My sim rig is as cheap as it gets so I don’t get much in terms of feel. I don’t really care to spend more on it too much