So if you compare a diesel to a petrol-hybrid, and you use the diesel's NEDC rating and compare it to the hybrid's WLTP rating, then number bigger!

Lets make a real comparison: The NEDC combined rating for the 2025 e-POWER is 5.4l/100km (FWD). The 2018 diesel version you linked uses 5.6l/100km, and the petrol 2018 version uses 6.2l/100km.

For a truly fair comparison you could have looked at the non-e-power versions from 2025, which come in at 7.4l/100km.