If I'm reading this correctly, they found post holes and a steeper ramp than expected, which leads them to believe that they both pushed the blocks up the slope

If I'm reading this correctly, they found post holes and a steeper ramp than expected, which leads them to believe that they both pushed the blocks up the slope and pulled them, through a "pulley system". I'm not so sure. I remember from high school that the pulley was one of the five simple machines noted by Hero of Alexandria, but he lived over 2000 years after the Great Pyramid was built. I have no idea if the pulley was possessed by the ancient Egyptians - absent additional evidence, I would assume that they likely just wrapped ropes around the vertical posts. That wouldn't qualify as a pulley (which is by definition a wheel and axle) but would explain the holes and the steeper slope, but wouldn't require a drastic change in how we understand that the pyramids were built.