I think this is a bit misleading. It's true that the average density of oceanic crust is greater than that of continental crust, making it less buoyant, but als

I think this is a bit misleading. It's true that the average density of oceanic crust is greater than that of continental crust, making it less buoyant, but also continental crust is way thicker and overall more massive, which is a huge factor in causing oceanic crust to subduct in addition to the buoyancy factor.