i’m on a new kickr 2020, and it does seem much harder to get to higher watts on flat roads than my kickr snap was.
i don’t think it’s as bad for me as the OP, but i have noticed that on my snap i’d ride at around 230-250 watts on flats, and on the kickr2020 i have to upshift into flats to get that high, and then downshift on hills to avoid bogging down, whereas on the snap i could hold a single gear. i can’t tell if this is just “direct drive vs wheel-on feel difference” or something weird about the kickr.
i was running trainer difficulty at 25% on the snap, and have bumped it up to 35-40% on the kickr, but it’s still noticeable.
for me, it’s not detracting from my experience, but my avg wattage over a ride is definitely lower since i moved to kickr from kickr snap. my wattage might actually be a bit higher on hills now, but it’s lower on flats.