Yeah makes sense. I certainly would not say the 120 feels like a 100, whatever a 100 is meant to feel like haha.
A big factor people forget with flex is the liner has a big impact too. The 120 uses the PrecisionFit Pro Tour and the 100 uses the LuxFit Pro Tour. the lux fit is going to be a softer more forgiving liner so if you want a softer overall fit and flex the 100 will probably be the best option. If you are used to the fit and feel of 100-110 boots the stiffer more performance liner in the 120 may throw you off a bit.
I personally would not say they feel much softer than most boots on the market. We benchmark test them back to back against a lot of boots in the market and try to aim to make the flex consistent to what is out there. So the 120 is going to be close to where most 120 freeride boots are. I also tend to think there is better consistency at the lower end of the flex scale. I would say most 100 flex boots feel much more consistent than the variations in flex of say 130 boots.