I don’t believe this is exactly true.
The ‘live traffic’ setting populates the world with AI planes based on their real flight paths and positions, but it’s still an AI plane in the sim.
I always fly with Live traffic, and I’ve heard many calls for AI craft to go around due to another AI craft lingering on the runway too long.
edit: yesterday I was overtaken by a Delta flight. He moved past at a correct pace. After a while I think the plane got updated with fresh data, and he accelerated to mach 1.5 for a bit until he was caught up to his correct position.