^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Yes, the Towers would have collapsed in a sideways manner, taking down other buildings in their path. The death toll would have been enormous.
In 9/11, the buildings essentially imploded, and therefore, did not do as much damage to the surrounding building.
I think what may have affected the death toll even more than hitting other buildings would have been the inability to evacuate people from the towers themselves. On 9/11, the delay between the planes hitting and the buildings falling allowed many thousands of people to escape to safety.