My concern was with the first two points changing to unrealistic values of 0C and 20C, instead of where those points used to be which was around 40C and 55C. I have no idea if maybe they are working on what had been reported about how CPU fan ramp up time could total something more like 10 seconds rather than one-tenth second.You are right, something is off with the bios fan settings, the values don't seem to correlate, i think the graph lines are reversed where temp should be fan speed percentage and vice versa.
As you describe, it can be confusing to look at the axis. When just looking at it, the vertical axis seems to be meant for the graphing of sensor temperature (left side) and fan RPM (right side), with a curve over the center with implied relationship to those axis (until you study it closely). Only when you click on a point does the curve get proper axis where the temperature is along the horizontal and the fan speed percentage is along the vertical. No idea why they choose such inconsistent UI, but you can see it in the picture(s) in citay's fan curve guide.