Calibration: zwift hub vs wahoo kickr

Hi. I’ve been using the wahoo kickr (version 3, I think) for a number of years without any issues. My experience on zwift seems very true to life. I calibrate it every week or so. Recently my partner bought a zwift hub and I’ve been trying it out. The “feel” when riding is different from the kickr but still very true to life. I think perhaps the hub has less momentum in the drivewheel which means you have to work harder on an undulating section of road, but perhaps I’m just getting used to a new bit of kit versus something which is a few years old. One noticeable difference however is when performing a spin down calibration. With the kickr the time from target speed (I think it’s 35 km/hr) to drop to end of calibration speed (approx 15 km/hr) is around 40 - 50 sec. With the hub the time from start calibration speed to end is only about 15 sec. Does this indicate a much higher resistance in the hub v kickr or perhaps I have done something wrong setting up the hub? The bike on my kickr has a quick release skewer while the bike on the hub has a through axle mechanism - could this explain the difference? I’ve checked that the through axle connector on the drive (cassette) side isn’t too tight which I believe may increase the resistance. Any help appreciated with this issue even if it is to assure me that it won’t really make much difference to my experience. Thank you.