The MNT Reform does not use Li-Ion batteries, resulting in much poorer energy density. It's going to depend on the cells being used but this is what I could see from the Reform Next detail page: 8× LiFePO4 cells (16000 mAh total). Assuming 2200mah cells, I think this nets you around 56 Wh in a 4S2P configuration, Li-Ion cells would be closer to 65 Wh.

According to Apple's website it seems a 14 inch macbook pro has a 70 Wh battery.