In case anyone else is wondering -

Neo:

  Height: 0.50 inch (1.27 cm)
  Width: 11.71 inches (29.75 cm)
  Depth: 8.12 inches (20.64 cm)
  Weight: 2.7 pounds (1.23 kg)

  Height: 0.44 inch (1.13 cm)
  Width: 11.97 inches (30.41 cm)
  Depth: 8.46 inches (21.5 cm)
  Weight: 2.7 pounds (1.23 kg)

It feels like they did everything they could so that the cheap MacBook with an iPhone CPU would not be lighter than the 1.5x more expensive MacBook with Apple Silicon

Thank you, from my cursory look of their comparison page, this is the information that was missing. But maybe that was a deliberate choice on Apple's part.