They take more risks because it works. That won't change unless society makes massive changes, which is unlikely to happen (much less any time soon).

Though the article wasn't too specific, it seems to me that it works because the risky stuff makes people stand out. Success in higher risk endeavors is much more eye-catching than success in the mundane. You see identical behavior in many other areas: startups that take a risk and succeed are more likely to get funding, anyone that does something unique (a risk itself) is rewarded heavily if they succeed.

I doubt it has anything to do with testosterone, and much more to do with perceived reward. Sure, that can cause an increase in testosterone, but it's definitely not required to do so to exhibit this behavior.