Let's distinguish between the aesthetics of rationality and the pragmatics of rationality.

Extraordinary - I don't believe I've ever heard anyone speak of the aesthetic aspects of rational thought before.

I'm not sure I agree with the concept, but it's something to think about.

It says, first, that it's a psychological fact that people don't adopt rationality as a conscious value until some other, already existing value is threatened by irrationality,

And when that value is threatened by the rationality? What then?

and second, that you won't keep developing as a rationalist without such pressure.

I suspect relatively few people have a deep desire for knowledge and understanding. They're usually the only ones I see developing as rationalists at all. If you don't have a need for the world to make sense, you tend to develop ad hoc methods for getting what you want. The need for systematic understanding is either present, or not.