You have just proved you haven't rode a cyclocross bike. Since those bikes' center of mass is higher than the road bikes it is really "nervous" on high speeds for example long descents.
But crit races are not like coming down from Stelvio kind of speed where nervousness counts. Crit races are exactly like cx races but on asphalt or at least where I'm in Europe ;)
I rode my cyclocross bike in the Swiss alps for months while waiting for my custom road bike. It was perfectly fine descending mountain passes.
As I said, that so called nervousness is overstated because people overthink it. BB height matter but for the most part we intuitively and inconsciously accounts for it and adapt. Also the difference is minute, from a 5 mm to 15mm. It is not like we switch from a road to a tall bike either. And guess what? A tall bike is pretty easily rideable, there are even people doing offroad on them.
A lot of people do not size their cross bike right - they ride a top tube length that is too short. Maybe this also helps with tight turning radius (which could be an advantage during a cross race).
not true - the "nervous" feel is because people also tend to ride cyclocross bikes that are shorter (top tube length). There is no reason a cyclocross bike cannot be designed with the higher bottom bracket AND a longer top tube - I never understood why the frames were designed like this in the first place (maybe for weight savings?)
That so called nervousness is greatly overstated. I think this is a US thing actually.