Everyone that rides a light road bike long enough eventually has this happen to them regardless of the bike. It is terrifying and many people never trust their bike again
after that, but it's not the bike.
Speed wobbles on a bike are always blamed on the components or frame, but are almost always caused by a harmonic interaction between the rider and bicycle. It is certainly possible for there to be a mechanical problem, but if there were it would show up at slow speeds as well.
This article explains the mechanism
The natural reaction when this starts to happen is to grip the bars tighter and that almost always makes the problem worse.
If you play around, you can get any reasonably light road bike to shimmy at lower speeds by "shaking" the handlebars. FWIW, I feel like this is much easier on steel alloy bikes than either aluminum or carbon bikes. I think this is due to the better spring response of steel compared to other materials. This is something that is worthwhile to mess around because you'll learn to recognize the initial oscillation and how to damp it out before it becomes dangerous.