Watts - Concept2 BikeErg vs Direct drive smart trainer

Does anyone have experience with comparing the two in terms of watts and power output? I cant seem to find a solid answer on this topic, but I’ve only ever used the bikeerg on Zwift and my sustained power output feels really low compared to when riding outdoors. I’ve heard that “watts are watts” but I’m curious if switching to a direct drive trainer would be a better move training wise than continuing with the erg.

If you mean that the bikeerg feels like you’re always riding steep uphill, then yes I would agree. I’ve noticed it feels like I always have to stomp it quite hard to keep the watts up and there’s no discernible difference between low drag high cadence and high drag low cadence in terms of endurance or feel. Still love the thing.