I am also experiencing this. Wahoo recorded my ride today with 1726 kj. It was a 3 hour 15 minute ride with an average of 214 watts. 1726 kj seems low to me for that duration and intensity. TR calculated 2371 kj from the power data from Wahoo which seems closer to what I expected for a 3+ hour ride. If I use the rule of thumb that 1 hour at 200 watts is ~750 kj, the Wahoo number seems to be significantly low.
Recording from a Wahoo elemnt with assioma duo pedals.