Poor choice of words on my side, beliefs aside, logic counts I agree.
Consequently next step below 150 would be 125, 100, 75, ...
...
No gripe here.
... 90 is a minimum operational value corresponding to 125 measuring value purely due to technicalities.
9.G that's a belief. 90 m segment from an Airbus does not satisfy 125m RVR. 100 perhaps, but not the 125 m requirement. Better yet, what about ATR?