I'm not sure. The media is pointing out specific cases but the question is what % of travelers on visa made it in/out without trouble. There is heightened focus on enforcement. They may have trained their software to have a lower threshold of social media posts for entry. So, I do believe that you're at risk if you've made controversial statements not in line with what US considers as friendly behavior.

Or if you have a criminal conviction of any kind that is many years old and was known on the application that got you the visa, like the German and Filipina residents. So the rules have changed - they are now saying that visas valid at the time of approval should never have been approved based on the circumstances at the time.