The power curve for any trainer or rollers was made at TrainerRoad while recording with multiple power meters, at a wide range of speeds.
That works well with a few caveats.
It relies heavily on the type of tire used. There is a wide range of rolling resistance variations between tires. It is even more apparent on trainers and rollers since they deform the tire more. Easy money that they used some trainer tire or regular road tire.
It also relies on tire pressure. Most often, you want to use the upper end towards the max rating for the tire and wheel. If my guess above is correct, then a pressure around 100-110 psi is likely.
The above matters even more with rollers because many of them do not include a resistance unit. They rely on tire deformation around the drums for resistance.
All that is to say that any difference above can impact the feel and reported power. So those variations are very likely at play since I’m guessing that you are using high end tubular race tires at a very high pressure.
That alone could lead to a much different level of tire deformation. I suspect that is a big part of why the rollers spin faster, with less effort.
And the other clear variation is the difference in the rollers themselves. The diameters matter a great deal, but there may be other differences adding to the issue.
But my bet is that a track bike setup is the core issue here. What are you running for tires and pressure?