It’s all about tyre grip apparently
If you lean the bike more than you, your weight will be more over the edges of the tyres, hence helping them ‘dig in’ and grip.
If you lean with the bike, or more than the bike, there is no weight over the tyres and they won’t grip so well, so can wash out.
Obviously, if the corner has a good camber or berm you don’t need to pressure the edges of the tyre so much as they won’t leaning in relation to the ground surface.
Go and see Jedi.